A/N

Another porno by me about alien mating. Based on A/B/O au. Mostly exposition on this first chapter.

Something was different here. Everything that was going on is different. But it wasn't the new android that infuriated Trunks. It was the scent coming from android Seventeen. It wasn't the same as his future self at all. It was unlike anything he had ever smelled, stronger than anyone else's. He didn't understand why. Or he did and he hated what it meant, and hated how it made his heart rate accelerate. When Seventeen caught sight of him his eyes widened. They blazed brighter than sapphires. It took every fiber in his being to hold himself back, to fight against the magnet pulling him towards his adversary. He felt his mission slipping away with every passing second.

He yelled and fired a blast at the android. He will regain control, no matter what.

The others yelled at him for his impulsiveness. He knew that the androids were fine even before the smoke settled. Even as Eighteen awakened Sixteen, Seventeen held his gaze. He smirked as if to taunt Trunks and then turned to the others as if his attack meant nothing.

Trunks refused to accept it.

He could accept that this timeline was different, but he can't accept this. Seventeen was staring at him the whole time his sister fought his father. His cheeks were red and he seemed to be going through similar conflicting emotions.

Seventeen knew what this was. According to his data on Saiyans, they had the ability to sort Humans into categories based on their scent. These scents were emitted by genes and triggered intense arousal between a saiyan and a human, as long as one's trait was homozygous and the other heterozygous. Humans with the recessive trait never experienced this sensation, but for the rest, just catching whiff of a Saiyan is enough to draw out their emissions. Dr. Gero took his into account, and gave Seventeen and Eighteen given the ability to suppress this trait and have the upper hand over the Saiyans. So then why? Why was he feeling so drawn to this stranger? Seventeen didn't feel anything from Vegeta's presence so the measures must be working. Was the new guy even a Saiyan at all?

Seventeen didn't know how to feel. He didn't understand why his face felt hot, and he hated it. He watched as the others speak to the stranger and heard someone call him Trunks. Seventeen instantly grasped onto it. It was the one thing he knew.

Suddenly, Trunks transformed and lunged at his sister in a fury. Seventeen didn't hesitate to stop, but reacted with a blow that would only incapacitate Trunks. Only after the battle did Seventeen realize the heavy scent left on his wrist. The emission must have activated after hitting Trunks. Seventeen pulled down his sleeve as if to hide an injury from the others, though they seemed completely unaffected by it. Seventeen bent down on his knees over Trunks' body.

"I wonder why those two had blonde hair," said Seventeen aloud. He pretended to inspect the other's hair, only to rub his wrist against his neck. If his theory was correct, then Seventeen had just marked himself as property. Not only did Trunks seem to know the most about them, he also had some vendetta against them. Which meant that his attraction to Seventeen must be torture. Plus, he didn't mind getting close to such a handsome, however foolish, man.

"Yeah, and I don't have data on that guy, either," came Eighteen's voice behind him.

Seventeen stood up. "Oh well, he's not our objective here." Seventeen doubted he could be followed just by smell alone, but he did hope to run into Trunks again. Another part of him was frightened by what this connection could mean, the scent was too intoxicating for him to care.

Before they left the scene Krillin asked them why they had to kill Goku. At the moment Seventeen himself wasn't sure, so he gave a simple answer. "It's just a game."

"But, killing Goku would be wrong!"

Sixteen spoke up, "No. I am programmed to kill Goku."

Seventeen shrugged. "There you have it."

He glimpsed at the fallen warriors.

"Tell your friends if they want to fight us again, we'll gladly take them on."

When Eighteen went over to give Krillin a kiss, Seventeen raised an eyebrow.

Eighteen ignored him when she came back to his side. "Come on, you're one to judge. I saw how you looked at that mystery guy."

Seventeen frowned and turned his back. "Whatever."

Only later, while Seventeen waited for his sister in the van, did he lift his wrist up to fully inhale the smell. He immediately felt hot and gasped. He felt his body changing as if he had taken a drug injection. He rubbed his wrist against his neck and whimpered.

"Seventeen."

Seventeen snapped out of it and realized his other hand was palming the front of his jeans. He quickly regained his composure.

"What is it, Sixteen?"

"I was certain that you were resistant to the pheromonal release of other life forms. Was I incorrect?"

Seventeen remained silent for a minute, flustered. "Don't worry. I won't be affected in battle."

"Hm…"

Seventeen tilted his head and rested against the window. His breathing felt ragged.

I shouldn't have tried to get more of his scent. Now I just want even more.

When Trunks regained consciousness, his father glared at him. "Get a hold of yourself would you! No wonder you hardly did anything! Did you think I wouldn't notice what was going on between you and the machine?"

Trunks felt his cheeks burn and realized his neck was on fire. He was horrified that his father noticed. "N-no! This… this never happened before, I swear!"

Vegeta analyzed him before turning his back and flying off.

"Wait!" Trunks stood up to following but then felt a hand hold him back. He looked down and saw Krillin beside him.

"Hold on, Trunks, you don't want to mess with him right now. He's pissed off that he lost to Eighteen."

"But…" Father knows. This is so humiliating.

"Look, I don't know what you guys were talking about but I would wait until he steams off to finish what you wanted to say."

Trunks stared at the ground in defeat. His father must have waited for him to wake up just to judge him to his face before flying off. He didn't know if he could even speak to him again.

Great. As if things weren't already tense between us.

Even worse, his body felt sexually frustrated after being so close to Seventeen.

It was while they transported Goku to the Kame house when Gohan made his point about timelines.

"Time must've changed a lot when you came back, like a butterfly effect!"

Trunks knew he was right. What else could explain everything that was going on?

Gohan continued, "But it's not like saving us would make your timeline disappear. If your mom knew that then why bother coming back at all?"

Trunks stared out the window. "She wanted to give this world the fighting chance that we didn't have…"

Trunks went to his mother's side by the helm. He lowered his voice and said, "Hey, Mom, I need to ask you something."

Bulma glanced at him and smiled as she flew the plane with ease.

"Of course, you can ask me any-"

Her sentence was interrupted by the ringing of her phone.

The call ended up sending the two of them and Gohan into a search for a run-down copy of his time machine.

When Gohan went off into the woods, Bulma noticed how tense Trunks had become.

She sighed before putting on a happy smile. It was the least she could for him. "So… what was it you wanted to ask me, hun?"

Trunks sighed. "It was stupid. Forget about it."

Bulma frowned. "No questions from a son of mine could ever be stupid!"

Trunks' face lifted a little and Bulma beamed triumphantly.

"It was just… one of the things that are different."

"Yeah."

Trunks inhaled. How could he possibly ask a younger version of his mother about his attraction to Seventeen? He knew she had developed suppressants around this time to prevent her Saiyan friends from harming loved ones. It wouldn't stop the strength of the scents, just give them more control over their instincts. Trunks thought about asking her for something stronger, something to cut off the attraction all together. When he thought about Seventeen out there, with his scent marking him, it was frustratingly arousing.

"It's just that someone I've met here… I think I've found my, uh, my true mate."

Bulma froze. Her face became pink when she fully processed his sentence.

"Oh wow… really?! That's great!" An awkward look came over her. "Um, just how much did your- did I tell you about that."

Trunks avoided her gaze. "You don't have to teach me anything, but… you told me that, for Saiyans, the scent from a mate stands out from anyone else's."

Bulma nodded. "That's right."

"But, my mate can't be from here right? I mean, this is practically another universe from mine!"

"I suppose… but I don't think it's necessarily a soul-mate thing. Or maybe it is and you were destined to meet her here? I guess your situation is as complicated as it gets."

"No kidding."

"I wonder how the bond would work when you're in two different dimensions… man. You'll have to team up with both me's for this."

Trunks shook his head. "I can't do that. That's why I wanted to ask you if there was some way to sever my emissions."

Bulma became upset. "Don't you know how rare it is for a Saiyan to find his one true mate? If you do that, then you'd never know what it's like to experience-"

"This isn't love at all! This is just DNA playing tricks on me. There's no way things could work between me and him. It's just a stupid alien mating process and I don't want any part in it."

Bulma gave him a look that Trunks was familiar with, one of sadness. "Your father was the same way."

"...What?"

"He was in denial too. But he knew how the significance of true mates. It was a part of his heritage, and I think accepting his feelings for me made him feel closer to his culture."

Trunks stayed silent.

Bulma came up to him and squeezed his shoulder reassuringly. "Trunks, as your mother I want you to be happy. As someone with past relationships, I assure you that having a true mate beats them all. I want you to feel that same happiness."

Trunks stared at the ground. "I… can't. It's android Seventeen, Mom. How could I possibly mate with him?"

Bulma's eyes widened. "No wonder you're so opposed to it." She sighed and crossed her arms. "This didn't happen in your timeline?"

"Of course not. These androids are different."

Bulma smiled. "Then if they're so different then your feelings must be right! It goes beyond DNA for Seventeen to smell different to you. As if one's mental disposition plays a part in how their scent smells to others…"

Trunks watched as Bulma scratched her chin and started mumbling theories to herself.

He sighed. "So what you're saying is, the Seventeen here is just mentally a different person than the one that I know?"

"Yes! Think of him as the good clone to the evil one. You shouldn't feel guilty for liking someone who so far has only killed that jerk Gero. I'd thank him for that!"

"What about his game hunting Goku?"

"Well… if he's as affected by you as you are by him then you should be able to 'talk him out of it.'"

Trunks felt hot and swallowed. He couldn't believe his own mother was encouraging him to be with Seventeen.

Bulma gave him a reassuring smile. "I don't want you to worry so much. Why don't we focus on the task at hand and see where we go from there?"

Trunks nodded. He had a lot to think about.

After that, they found the copy of his time machine, along with a strange exoskeleton Gohan found nearby.

Piccolo later on revealed that the shed skin belonged to Cell, who arrived one year before Trunks ever showed up.

Two time travelers on Earth at the same time could be another reason behind all these changes.

Piccolo interrupted his thoughts. "He said that his goal is to absorb androids Seventeen and Eighteen to achieve his perfect form.

Trunks felt still. There was one thing he knew for certain, and that was that he wanted to talk to Seventeen at least once. As Trunks came to grips with their situation he also felt responsible for his safety.

He needed to train to defeat Cell, but his Father was a harsh training partner. A couple weeks into their stay in the hyperbolic time chamber, his father surprised him. "You're too distracted, Trunks! Stop focusing on that android. You're not getting anywhere with him if you can't stop Cell."

Trunks was shocked that his father said something reasonable to him.

Vegeta looked away from him. "Don't run away from your problems. Just accept your fate."

"Um… thanks?"

His father grimaced at him. "I'm just telling you to stop thinking for a whole year. Don't waste my time with your dramatics."

Trunks sighed. Still, he felt kind of touched to receive advice from his father.

When they got out the chamber, he wasted no time flying to where Cell was confronting the Androids. But he was too late.