An Oath of Mercy || UnderFell Sans x Reader

twelve

You left Sans' jacket and clothes on his bed. You debated for a long moment with your hand on the collar he'd given you, but decided if you were leaving the Underground, you didn't need his protection anymore. Before you left his room, you considered leaving a note for him to find, but ultimately decided it was probably better to leave that harsh goodbye as is. Knowing him, it was likely a similar situation to Papyrus, and that combined with his confession of his feelings right before your boyfriend appeared probably just made everything 10x worse. His confession was so sudden, and if you were given more time, you weren't really sure how you would've reacted.

Despite knowing that Leon wasn't planning on killing you now, you couldn't help looking back at the past 2 years with him without the rose-tinted glasses. He was a great guy, no doubt about it, but you could see the cracks in the relationship with clear eyes now. You wore the pants in the relationship, and while there's no problem with that, he had no spine when it came to anything, especially decisions of importance. When you were stressed from the college pre-med track, you took it out on him, and he never did anything to stop you. While that seemed noble and thoughtful at the time, now it was obviously bullying on your part. He deserved better than that, and you needed a man that could tell you to stop that if you ever wanted to recognize your flaws and change for the better. Someone like Sans-

You blinked, just now realizing you were staring at nothing as you walked with Leon and Flowey. Your old clothes were back on—your blood-free black shirt, red skirt, socks, and hiking boots—and you couldn't wait to throw them all in the washer. Your lab coat was bunched up in your arms—a little dirty it seemed. As you brushed it off, Flowey nudged your cheek.

"What were you thinking about?" he asked quietly, the compassion back in his voice. Since you'd all left the skeletons' house, he seemed to be in much higher spirits. But, you supposed, he was finally getting out of this hellhole. He had every reason to be hyped.

"Just...a lot," you said honestly, sighing tiredly. Leon was up ahead, leading the way through Waterfall back to the Surface with occasional instructions from Flowey. The route was rather straight-forward, and you met Papyrus along the way. He refused to talk to the guys, but he did happen to tell you he and Undyne were going to be in Snowdin for a while. Even if he acted cold and uncaring, he was subtly removing Undyne from the equation. So you made sure to thank him—even though he just responded with a disinterested "HMPH".

With every step, you felt regret sink its claws deeper. The monsters needed you—but they were acting out because of your influence. The skeletons wanted you around—yet they both told you to "fuck off". You had a whole life you were throwing away by staying in the Underground—but you were dooming the whole Underground by leaving. Your heart wanted to be with Sans—but you had a boyfriend. To say you were conflicted was an understatement.

"Talking about it helps," Flowey said, smiling lightly. He sounded like he was quoting you. You gave him a shaky smile in response.

"So much has happened to me, I feel like I've been through multiple lifetimes." You laughed, well-aware that it sounded silly. "And I guess I wonder if I'm really making the right decision."

"Of course this is the right choice! We don't want to be stuck in this hellhole a second longer." Flowey smiled brightly. But something about how he said that made you frown.

"Well you've wanted to get out of here for years. I'm not like you."

"What do you mean?" He tilted his head, confused. "That's why we joined up in the first place: the same goal."

"Yeah...but plans change." Your frown deepened as you stared at the ground under your feet. Flowey moved into your field of view, his mouth in a concerned line.