Just to explain the setup a little; this takes place at Sidonia manga, just a little after they recruited Teruru, and they haven't started getting ready for the war with the Large Mass Union ship. For NGE, just imagine at the end of 2.0, the gauna invaded earth, Shinji called upon the ceremony to rescue Rei from being consumed and that's where his story ends and begin. If I get to write until that far to explain everything, then great, if not, just enjoy the ride first…

….

It was just another day in the space of Lem system….

"What is the sum of a man, but his awesome deeds, his privilege to use the latest Guardian techs and his home; warmed with the flesh of women, transsexuals and alien tentacle."

"Tsuuruchi, youre on team comm. Keep your loser thoughts to yourself."

"Yess ma'am. Zipping my mouth, Squad leader Samari." Tsuuruchi said as he drew a finger across his visor where his lip was.

"If I were to go out today in glorious battle, would you hold my body to your bosom tightly, and fulfill the last wishes of your subordinate?"

"I would put a shell through your face before you get eaten by a Gauna. That's all I promise. Now shut the hell up."

Sixteen Guardian, making up four squads plus the special duo Nagate and Tsumugi flew towards the small asteroid of 2km wide. A single Gauna true body was propelling the rock towards Sidonia. The plan was simple, two squads would burrow nukes into the asteroid while the other two provide covering fire. When the Gauna body is revealed the Guardians will take it out through conventional methods.

Commander Aide Yuhata stared at the strategic display longingly. If only she could be out there with Nagate…and Izana. The success rate of this mission was above ninety percent, calculated through information collected from previous battles and all known Gauna factors. She wouldn't rely on numbers alone, those gauna's occasionally have a good surprise. If the asteroid has a Benisuzume class, or two, the numbers given by the mainframe would go down to single digit.

"Tanikaze, Tsumugi, maintain at maximum firing range." Yuhata called out.

"But Tanikaze, if the Gauna decided to show itself, someone might get hurt." Tsumugi voiced her concern only to her partner.

Tsumugori fired its reverse thruster as it gets into position. "The new pilots need the actual experience. There is no better teacher. Besides, Samari and other senior pilots are there to give orders."

"I see… you sure think highly of Samari don't you?" Tsumugi playfully flicked her tail at the mecha's behind.

It was time like this when full battlefield awareness has its pros, or cons, depending on who you asked. The pilots on reserve watching the live battle feed went 'awww'. Izana should be numb by now, with these random display of affection between Nagate and his chimera partner. Her mechanical arm curled into a death grip for a moment before a stream of images sent directly to her made her cautious.

" Movement detected within the asteroid body. The drones are mapping out the subterranean now. Lots of hiding places for ambush."

"Copy that, Izana." Samari replied.

Two teams went into the opposing hemisphere with the objective of drilling and planting nuke into the asteroid, but seeing that the huge rock was actually quite cavernous Tsuuruchi had the great idea of just doing some space caving and dropping the nuke into the middle of it.

"Hey you should check this out, the cave system is just wide enough for a Guardian to fly through. You might think the solo gauna could be a guardian type but that's like too much coincidence right? I mean, whats the chance of me flying right into Benisuzume type and getting stab in the face? But before that, I might get to make out with a hot placenta in my cockpit."

Nagate coughed and steadied his mech as his machine was prodded by a really strong tail.

"What does Tsuuruchi meant by 'make out' and 'just like Tanikaze'? Are you alright, you're coughing quite badly."

"Tsumugi, focus on the mission please. Ignore the mindless talk of Tsuuruchi." Yuhata would love to see Nagate getting slammed on the floor until his face caved in but she got to step in. He's the only reliable ace around.

Tsuruuchi moved a few hundred meters deep when he noticed some weird movement on his sensors. The true body stayed motionless in the center, still protected by layers of rock and minerals. It could be just some tentacle. He packed the railgun away and took out the submachinegun, a close quarter weapon proven by the ace Tanikaze.

"Gyahhhhh!" A female voice screamed over the comms.

One of the Honoka girls vital display popped on his HUD and turned into an X. Tanikaze checked her last known position dissappearing into the cave, very close to Tsuuruchi current position.

"I'm going to get her, Tsuuruchi out." The veteran pilot really wanted to tell his teammate how badass he sounded. He decided to save it for later when he rescued the chick.

Three more frame dissappeared into the cave network in quick succession. Izana issued a full blown alert to all teams. All pilots saw blurred image of a Guardian sized creature taking one of their own. They could be dealing with more than one Guardian type gauna here. The worst part is that the Gauna is partial cloaked from her sensors, revealing itself only to visual contact.

"Tanikaze, our friends are not prepared to deal with Benizusume type. We need to join the fight too." Tsumugi pulled on her partner's arm while she voiced her concern.

"Be patient Tsumugi, Yuhata ordered us to support from distance. We must not disobey her. Beside we still do not know whats the Gauna capable of." Before he knew Tsumugi, Nagate would be the first rushing headlong to save his friends. What made him hesitated this time, he wonders.

The shockwave from Tsumugi speeding towards the asteroid pushed Nagate's airframe aside. Was he ever so reckless too?

Tsuuruchi floated gently into the caves, towards the position where all the last known position converged. If it's a boss type Gauna waiting for him there, he's in way over his head. He always had more balls than skills.

He saw the signature of five non operational frames ahead of him. The Gauna successfully duplicated the ID signal of Guardians before, it wouldn't be a surprise if its an ambush lying ahead. He pushed on anyway, moving his frame stealthly on instinct.

His sensor beeped again, right in front of him. No gauna presence, just movement. Tsuuruchi emptied his SMG into the darkness, before he realize that Izana reminded everyone that the special Gauna seems to be partially cloaked from sensors.

Last movement shown was right on top of him. Tsuuruchi took a step back and turned on his headlamp, turning the light onto the ceiling. A purple gauna holding the ripped arm of a Guardian dropped on his mech. The pilot brought his mech's arm up in a cross block, taking a wrist blade through. He fired his head mounted Higgs cannon as he fell on his butt. The gauna did a backflip to avoid and kicked against the ceiling, landing on all four.

Tsuuruchi looked in disbelieve as the gauna pulled that human like movement. Copying a Guardian and jetting around one was thing. He turned on his leg jets and put as much distance as he could while he reloaded his SMG. The purple beast sprung towards him and closed the gap in no time.

Damage alert flashed brightly in his HUD as the mecha's head has pummeled into the ground again and again. With the purple gauna straddling him, Tsuuruchi had nowhere to run. He tried to aim his SMG at the gauna's head but all it did was pissed it off. Now the gauna was beating him with his torn off arm.

"Hull integrity at thirty percent!" A few more whack and the cockpit would be crushed. Tsuuruchi wondered will he die on impact or will he be so badass to be tentacle pulled barely alive out of the frame, athen he got to say a one liner and spit at the gauna.

"Let him go!"

Ahh, his knight in shining armor, coming to save his worthless butt before Tsuuruchi became gauna food. If given the choice he would take Samari but a giant alien girl is just as good right now, he wouldn't complain though, when the alternative is getting your face punched in and eaten alive.

The humanoid gauna rose to height still holding the airframe head's on one hand. Both Tsuuruchi and Tsumugi had a good look. Unlike Benizusume and other guardian type gauna who wore flesh like armor, this one had smooth, machined plates of armor covering its body. It got the face of a demon with pair of eyes that shone with gold and a single horn with the same length as its head.

What started as a mission with a high success rate goes to hell in an instance. Analyst at the bridge gasped with horror as they received the video feed from Tsuuruchi's unit. Gauna had evolved its threat over time, mostly from copying human strategy and weapons or improving on past weaknesses.

"Our scans shows the….new Guardian type gauna is covered in actual heavy metal plates stronger than husk material. We have no other Gauna matches in our databases."

Yuhata knew all the main gauna type with a threat level capable of defeating a Guardian. Did the Gauna developed this weapon from the defeat of Benisuzume? If those monsters are evolving so fast, Sidonia is so screwed royally.

"Its just one Gauna. Tsumugi, try to lure it out and team up with Nagate. Drill teams, continue with your mission." Yuhata was cautious here. The last Gauna superweapon did defeat Tsumugi due to her carelessness.

"Ma'am, permission to designate the new Gauna type as Horny One?" One young analyst suggested.

"Denied".

….

Tsuuruchi felt like he was shot through a railgun into the side of a moon. If he survived this, he would end up with a bunch of medical steel up his neck. Right now, he is living his dream, dying in the arms of a woman.

Tsumugi caught the airframe being thrown at her like a planetary buster missile. She heard her chest cracked as the impact throw both of them backward. She heal fast but it still hurt. The armored gauna was not going to let them go easily.

"I cannot escape with Tsuuruchi."

As soon as she put down the airframe, she lashes out with her claws. Tsumugi wanted to cut loose for a while now since her encounter with Benisuzume didn't go too smooth. This strong gauna would be the focus of her anger.

The horned gauna dodged every strike and eventually caught both of Tsumugi's wrist. She noticed this earlier, the peculiar habit of the gauna to stand on solid ground instead of flying. She tried to use this to her advantage and levitated closer to the cave ceiling, trying to slam the gauna. To her surprise her body was lifted at an angle, her legs pointed toward the ceiling no matter how much flight power she force out.

"Eh, the gauna wasn't flying on the opposite direction, how can it cancel out my pull?"

She saw a flash in its uncaring eye before she felt someone put an accelerator round through her face. The armored gauna pulled on her wrist and met her face with his. Cracks started to appear on her mask after a few more headbutt.

The scene at the battleroom got rowdy as the reserves shouted among themselves.

"Dammit, if I'm out there, like hell I would let that bastard do that to Tsumugi."

"Now they got headbutt, soon , they will have balls kicking. Its game over man, game over."

A moment of silence took them when the camera feed from Tsuruuchi moved.

….

The armored gauna stood still as a kabi blade pierced through where a human heart would be. Slowly the length of Tsumugi's tail lifted the gauna off his feet through the hole in its chest. The chimera girl held her head in both hands, blood dripping down her arms.

"You know girl, if you want to thank me, I'm still here, holding on to life until I get a wet sloppy kiss that last at least five minute, maybe more, to send me to the afterlife."

"This bastard….he messed up my face!"

"Okay…you take your time."

At Sidonia's bridge, the crew cheered too when they witnessed Tsumugi comeback. Still it was too early a victory as no true body foaming was detected. The gauna struggled and ripped the kabi blade from her tail end. Tsumugi didn't have a chance to retract her appendage as the gauna swung the blade at chest level, cutting a good piece of tail away.

She went wild with her claw attacks, not caring if she got hit just to get a swipe in. The humanoid gauna patiently took the attack, its armor on the forearm and abdomen tearing away from the furious attacks. When it saw a small opening, the purple gauna shot a spear finger at the chimera's neck.

Despite not requiring to breath, it still hurts a lot to have her neck punctured. The battle now turned around with the chimera girl on the defensive. The armored gauna took a human stance with a foot forward and both hands raised to guard the upper body and head.

The bridge looked in shock as the armored gauna delivered lightning fast kicks to the chimera. When a gauna engage its enemy, its to destroy or consume, sometimes both. There was no data that a gauna took pleasure in a fair battle or they just want to cause damage without killing its prey.

Yuhata cursed at the screen, despite having all the firepower of Sidonia at her disposal, she could do nothing for her friend down there. She watched as she took kicks to the rib that would cut a Guardian in half. She had no choice now, she had to send in Nagate. Its all or nothing.

"Give me status on the drill team now!" The mainscreen switched just before she saw Tsumugi tentacle dress get ripped to shreds.

….

Tsuruuchi couldn't feel his legs, hell he could barely feel his left arm, his so called golden arm. And its not because he use it to hold his cock. He got one shot to help out Tsumugi. Even if he manage to take the shot, a kabi blade through the chest couldn't defeat the gauna so it was slim chance he could do any damage. If he fail, he would annoy the armored gauna and get killed first.

"An awesome hero like me can't just watch a girl get killed without doing a thing."

The thing with gauna is that, despite the organic look and feel, they got almost none of the weakness of an organic being. The cranial system on a gauna, you can rip out its brain and spine and it would still tear you a new one because the arms and tentacle wasn't really controlled by the brain. But this armored gauna moved and acted, almost like a humanoid being. Maybe the gauna got ahead of itself and imitated human limitation too.

He overloaded the Higgs cannon for one decisive move. When the gauna stop for a split second, he would put a beam through its eye, the only part where its not protected and it's a direct path to the brain.

"Tsumugi!"

Holding the drill equipment like a lance, Nagate charged the armored gauna. Tsumugi moved out of his path and held the gauna down with her tail, as their enemy has proven to be very agile. The gauna was immobilized but still manage to catch the mining drill with his barehands. Sparks lit up the cave as the gauna held its ground.

This was the moment Tsuuruchi waited for, where the enemy puts all its focus on defense. A stream of overcharged Higgs particle beam pierced the gauna's eye. A moment of weakness was all Nagate required to pin his adversary against the cave wall. The pilot set his jets to maximum burn as he think of a method to defeat this monster. Sensor detects no true body on this gauna so he has to buy as much time as possible. The kabi blade should have caused serious damage if this happens to be a case of rogue placenta acting on its own but the armored gauna has proven to be really resilient against anti-gauna strategy.

Wait…what if this monster is not a gauna…

"Tsumugi, cut his face off!" Nagate asked her partner while he still push on with all the force the airframe gives.

"I was just thinking the same thing!" Tsumugi would have licked her lips if she had one. She needs to ask Tanikaze if he prefer her to have lips just in case he wanted to.."Ahh stop thinking such thoughts in the middle of battle."

She picked up the kabi blade she used earlier and threw herself at the armored gauna. Her foe stopped resisting against the drill and tried to raise his arm to stop her advance but she had a good start so she was faster. When she pierce the gauna's neck, she noticed some placenta flesh stuck to the back of its neck sizzled away. With no time to ponder on its importance, she press her other fist on the handle and turn the blade all the way across. The gauna's throat open up like a can of food. Red blood sprayed onto her face. Tsumugi tasted it; just like human blood.

Despite the injury, the gauna still struggled with all his might while Tanikaze's unit was pushed to the limit. The HUD told him the machine would overheat in less than a minute.

"Nagate, hang in there we're sending backups over." Samari called him.

The ace pilot activated all the manual override in his mecha to squeeze extra performance out of it. "Forget the backup, how fast can you take out the main gauna?"

"We got the mines in place, but you need to get out of the caves first. The whole thing will fall on you." Even as Samari said this, she could predict that Nagate was going to tell her he got something dangerous in mind.

"Don't worry about me; just detonate it now. Tanikaze out." The pilot checked his inventory for remaining weapons and fuel.

"Tsumugi, grab Tsuuruchi and give me some covering fire. I'm going to let go now."

His partner shoved Tsuuruchi into her abdomen reluctantly; she didn't like having another guy inside her. Tsumugi then picked up the railgun she left on the floor earlier. The very instance Tanikaze let go of the drill and fired his retro thrusters, she squeezed a few shot onto the gauna. The escaping mecha too unloaded all his submachine gun rounds and Higgs cannon while flying backwards. The monstrous gauna who was still momentarily pinned took all the firepower, while it pried the drill off his chest.