Sans and Frisk spent the rest of the night together in the room they had rented at MTT Resort. Sans wrestled with the promise he made to Frisk all night. He did not even want to entertain the possibility of killing the person he loved the most, but knew that if the opportunity came, he would have to do it. Sans made love to her the entire night, as he didn't know if he would have to fulfil that promise soon. He wanted to keep her close for as long as he could. He couldn't help but feel a huge sense of dread in the back of his mind that he would end up having to keep that promise.
The next morning, the sun draped into the hotel room through the curtain they had left open the night before. The sun danced off Frisk's bare back and she was fast asleep. There were no signs that she had had any nightmares. It seemed like this was the most she had slept in a really long time. Her brown hair was tinted gold as the sun hit it just right to make each strand of her hair shine. Sans loved her so much and it was painful to think about the promise he had just made. He wanted to protect her and having to fulfil that promise would break the one thing he had been trying to do this entire time.
"I love you." He whispered, kissing the nape of her neck. She stretched her body and readjusted herself but did not wake up. He could stare at her beauty all day. The only thing Sans wanted to do at that moment was hold her close to him and never let her go.
It pained Frisk to have to entrust that promise to Sans, but she knew he was the only one that could stop Chara in case anything went wrong. Frisk was even ready to have to end things herself if Sans did not make the promise for her, but she knew that Chara would prevent her from harming herself. After Alphys treated her brain waves, she began to think clearly about how to stop Chara from taking the Underground and the surface over. She didn't want anyone to get hurt.
It was nice to be able to take a few days off and spend it with the one she loved. Frisk had gone back to her job working the hotdog stand in Hotland. It had gotten busier during the afternoon, which was strange, but she had fun speaking to everyone anyway. As soon as the crowd died down, she took a break and sat down at the stand, organizing her inventory and taking a breather.
The feeling of being watched was back.
"Fuck that lizard," Chara's voice returned to Frisk's mind. "Those brain waves you send me. They're excruciatingly painful. I didn't know you loved to inflict pain like me, Frisk." Frisk was horrified. She felt the resonating feelings Chara had been having. The treatments had been hurting Chara. As much as she wanted Chara out of her, she was not about to resort to hurting another human being.
"I… I didn't know they would hurt you." Frisk responded.
"You're one interesting human. You're actually worried about me? The one who's been trying to take your body over and destroy all humanity?" Frisk couldn't help it. She hated hurting people, even if the person had been hurting her. She was too much of a pacifist. "I'll never be able to understand you. We're very different, you and I."
"I mean. We can't be that different, right? We're both humans. Two of the eight humans that have fallen Underground. We both have determination. We both are passionate about our goals. It's not much different."
"Passionate about our goals? Why? What's your goal?" Frisk paused. Really, her one goal was to keep everyone in the Underground safe. She wanted to do that without hurting anyone. "What a stupid goal. But I admit you are passionate. I will give you that much."
"Is it really a stupid goal to want to save everyone?"
"No one gets to have a happy ending. This world is horrific and deserves to be destroyed. I lost my chance at a happy ending a long time ago."
"It's never too late for a happy ending, Chara." Chara paused. Frisk paused too. Did Chara really deserve a happy ending? No, probably not. Was she going to try and find a way to give him one?
Absolutely.
"You're naïve. There's no possible way you could find me a happy ending."
"You must not know me too well, despite being in my head for a while. I'm very determined."
"So am I, Frisk. So am I."
"Absolutely not." Sans shut Frisk down. "Are you crazy? You finally get some peace of mind with Chara not being in your head and you're trying to refuse the brain wave stimulation?"
"Like Alphys said, we don't know if it's doing any unnecessary damage to my brain. I'd rather not wait to figure it out." But that wasn't the real reason Frisk stopped. She didn't want to hurt Chara, and she wanted to try and convince him not to hurt anyone. If it was possible, she was going to try and find a way to save him, too, but there was no way she was going to tell Sans that. He would not have liked it.
"S-She's right Sans," Alphys said. "I literally have no idea what the side effects of this stimulator would be. I didn't even really want to try the stimulator the first time, but Frisk insisted so we tried it. It works, for the time being. I think we should just focus on rewiring the determination extractor." Sans grunted angrily. He didn't want to have to see Frisk have nightmares every night. It was the worst to see her like that. Frisk put her hand on his arm.
"It'll be fine, Sans," Frisk said. "We'll find a way to make it work. I'll try and find a way to suppress Chara without the brain stimulator somehow." Sans had a strange feeling that Frisk was hiding something but decided not to pry more. It was hard enough for her to admit to him that she wanted him to kill her if anything went wrong.
"Ok," Sans surrendered. "Whatever you think is best, Frisk." He kissed her on the forehead. "Let's get started then. Let's run more tests. Are you ready Alphys?" Alphys nodded, and hooked Frisk up to her monitoring cables. Sans ran toward the determination extractor and began to work on rewiring it. He put his entire being into trying to figure out how the machine worked, so that he would not have to keep his promise to Frisk.
Surprisingly, Frisk didn't feel Chara's presence much that day, despite tests being run. Maybe Chara was starting to have second thoughts about taking Frisk's body over. Frisk wanted to ask them if there was a way to remove Chara without hurting him in the process but figured that would get a lot of pushback from Sans. After a few hours, Sans stepped outside the laboratory to take a break from reengineering the DT extractor. Frisk took this opportunity to speak with Alphys.
"Alphys," Frisk said. "Can I talk to you?"
"Y-yeah, of course Frisk!" Alphys responded. "What's u-up?"
"You have to promise me you won't tell Sans any of what I am about to tell you. Please Alphys. Promise me." Alphys hesitated at first, but figured it had to be serious if Frisk didn't want to tell Sans about it. She promised. "I… have something I might want you guys to do. But I know Sans wouldn't like it. That's why I wanted to ask you." She confessed to Alphys that the brain stimulation was hurting Chara, and that Frisk didn't want to hurt another human being. From some of the conversations Frisk had with Chara, she felt as though she might be able to save him, too. "So this is my request… I want you to find a way to remove Chara from me without hurting him. Maybe once he's away from me and isolated we can talk to him or something and figure out exactly why he wants to hurt so many people. He's been so miserable and unhappy, Alphys. It's not fair that he doesn't get to have a happy ending too." Alphys was surprised at Frisk's confession.
"Uh… Give me a second to think, okay?" Alphys knew Frisk was right: there was no way Sans would agree to a plan like this. Sans's priority was to save Frisk from Chara's evil plans, not caring what happened to Chara himself. Frisk wanted to save Chara. She was being selfless even in this time of distress. She really was an amazing person. "It would take a lot of extra work, I hope you know that. A-And we would have to do a lot of tests on our own, without Sans here. If he found out what we were doing, he would absolutely freak out!"
"Whatever it takes, Alphys. I'll just tell him we're hanging out a lot, that'll be easy to get past him."
"You do realize there's a risk of him trying to destroy everyone once he comes out, too."
"Then we need to take steps and make sure that doesn't happen. You can create bodies, right? Like Mettaton's? If you make one you can control, we can isolate him and make sure he doesn't hurt anyone."
"Okay. I'll… I'll do it. I'll help you save Chara."
Frisk and Alphys had created a secret agreement to try and extract Chara to be able to save him. The feeling of saving another human soul filled Frisk with determination.