((A/N: Thank you to Meg, JashertheDarkened and Aperture Survivor for your reviews!))

Snapping out of his shock, Sans moved into action, he raised his hand and held onto Gaster with his magic, and with a flick of his wrist sent Gaster flying past them and onto the lounge room couch behind them.

The white in front of them disappeared and Sans sighed in relief, showing Frisk that he had released his magic on the door and closed it. He looked incredibly tired, but he did not stop to rest and hurried to Gaster on the couch, checking his Soul.

HP: 1/1500

Frisk felt a shiver in her soul, that was too close, just one more HP and Gaster would be dust, and this would have been for nothing. She looked to Sans, and what she saw filled her with concern; he was shaking and the look of guilt in his eye-sockets had come back.

Frisk flinched in surprise when their front door suddenly opened.

"THERE YOU ARE BROTHER AND SISTER! I WAS SO WORRIED WHEN I COULDN'T FIND YOU AT GRILLBY'S. WHO IS THIS? IS HE A RELATIVE OF FRISK'S?" Papyrus looked down and Gaster curiously.

"pap! thank goodness you're here, dad's been hurt, he could really use some healing magic right now." Sans looked at Papyrus with desperation in his eye-sockets. Papyrus looked confused, but quickly went to work, his eye-lights glowed green and he gently touched Gaster's soul. There was a collective sigh in the room as Gaster started to rapidly regain his health.

Papyrus, however, narrowed his eye-sockets, and Frisk couldn't tell why until the HP suddenly stopped rising half-way.

"what's going on, pap? why'd you stop?" Sans asked.

"I HAVEN'T BROTHER, IT APPEARS THAT THE REST OF THE DAMAGE MUST HEAL NATURALLY." Papyrus explained gently, although he still didn't seem to know what was going on, Frisk knew that Papyrus was at least capable of seeing that his own brother was distressed.

"but pap, you're one of the best healers out there." Sans protested.

"No, that is correct Sans, there is nothing Papyrus can do." Frisk had forgotten that Gaster was still conscious until he had spoken. Sans seemed to have forgotten to as he turned to Gaster in surprise. "The weapon used by Falmercia is made out of her demonic magic, pure evil, such damage cannot be healed with the use of magic and only with time."

Gaster's voice was tired and wispy, and as Frisk listened, she suddenly realised that he was also speaking in another language. As for how she understood, she could only reason that it must have been a skeleton language or something, and she must have been able to understand it magically.

Sans seemed to have calmed down now, and his eye-sockets narrowed, "dad, how do you know this? what's going on?"

Gaster frowned, face turning grim, "Falmercia was trapped in the void with me, and ashamedly, I had exchanged information with her to chase away insanity that would have come from isolation." Gaster's eyes flashed with urgency, "Sans, you must understand what you are dealing with!" Gaster moved to try to sit up but Sans held him down.

Gaster quickly gave up and explained from his lying position, "Falmercia is a demon that has been trapped in the void for several millennia, and she has been planning this escape since I fell into the void. A long, long time ago, she was the strategist behind a kinship of demons that conquered almost the entire world, and would have succeeded in controlling the whole world if Falmercia hadn't fallen to her own sin. She abandoned her kin and they fell without her, humans and monsters allied together and captured her and eventually worked together to trap her in the void, sealing her in with a barrier… a barrier she needed a monster and human soul to destroy."

Sans and Frisk looked at each other frowning, a new understanding of what they had just done. For humans and monsters to have teamed up together in the past, Falmercia must have been a big deal, and they had just helped her escape.

"She is incredibly intelligent and extremely dangerous, you must be careful!"

Gaster also appeared to be feeling guilty and it was obvious to Frisk why, Gaster had said that Falmercia had only begun to plan her escape since he had fallen, so she must have needed some of the information that he had traded.

Frisk figured that she would at least try to use that information to good use, "When I'm around Falmercia, I feel more tired than usual, is that her magic?"

Gaster smiled somewhat proudly, "That is correct, I commend you for your observation. As a sloth demon, Falmercia has an aura of sloth, that increases in potency as she gains power, she is weak now from her time in the void, but I fear that if she gains more souls, it may become so powerful that we would no longer have the energy to fight back."

Gaster's gaze shifted back behind Sans and Frisk and at the wall, "Of course, that only refers to those who possess both a soul and a body, your highness."

Frisk shivered and Sans' eye-lights went out, "chara."

Chara revealed herself, standing awkwardly, "Um… Hello!"


Falmercia took her time walking through Waterfall. Stage one of her plan was complete, time to move on to stage two. Stage three, would require a lot of work, too much effort as far as Falmercia was concerned, so she had decided that she needed to acquire some help, and she just so happened to be perfectly equipped to do so.

Smirking when she saw the particular prey she had in mind, she stopped in her tracks and gave a lady in a suit of armour a wave. Undyne stopped in her tracks also, before approaching Falmercia.

"Hi, you're Undyne, right? Captain of the Royal Guard?" Falmercia asked, playing the part of a civilian requiring help to lower Undyne's guard.

Undyne hesitated, but took off her helmet, "YEP! That's me." Undyne's unpatched eye narrowed, "Is there a problem? Someone causing trouble?"

Falmercia smiled, before offering her hand to shake, "Forgive me, it appears I have forgotten my manners again, I am Falmercia."

Undyne looked at Falmercia's hand before accepting it, "Nice to me-" Undyne shivered on contact with Falmercia's hand.

So, she can sense malicious intent, all the better.

Undyne stared at Falmercia's smiling face for a few moments, Falmercia knew that Undyne had sensed her intent, although she also knew that Undyne didn't know exactly what it was.

"As for why we're having this conversation, I heard that Asgore was just one human soul short of breaking the barrier, is that true?" Undyne nodded suspiciously. "Well, I have a human soul that I'm ready to exchange for a favour." Falmercia raised her hand to reveal Frisk's previous soul.

Undyne's face filled hope and wonder, she no doubt thought that all her dreams were coming true. This was often Falmercia's favourite part of making deals, when just after she offers something too good to deny, and the person she offered it too forgets caution and a very important fact regarding Falmercia's true nature.

"Favour?" Undyne asked, before shaking her head, "What am I saying? I'll do anything!"

Bingo. "Deal." Falmercia smirked, and for a second doubt flickered over Undyne's face, which cut off into shock as Falmercia plunged the soul into Undyne's chest and into her soul, forcing Undyne to absorb it.

"Well, now I have fulfilled my end of the deal," Falmercia said, sadistic pleasure on her face as Undyne fell to her knees and clutched at her chest in pain. "And you did say you would do anything."

Undyne's form began to change as she completed absorbing the soul, it was a mostly familiar form, almost identical to her 'Undyne the Undying' form from Chara's genocide runs, except the heart on Undyne's chest was broken in two.

"So here is what I ask of you," Falmercia began to cackle, "I need you to be my obedient soldier."

Undyne's transformation was complete, and she finally opened her eyes, both were pitch black with a green, glowing pupil.

"Yes ma-am."