When you found out that sans had memory of the different timelines, albeit limited, you had to talk to him. He brought you two to a hilltop he had found, that didn't have many trees blocking the sunset. You started to talk about what you remembered from the timelines, to fill in the gaps he had and see if he would still want to be friends.

"kid, i can tell whether it's you or chara."

You look up at sans. He's trying to forgive you, but he's wrong. "I can't always tell if I'm me, sans."

"i can't always remember you, but it doesn't take long for me to tell if someone's human or not. frisk, don't beat yourself up about things that demon did in other timelines. we're all on the surface now, everybody's happy, and they're alive."

He shouldn't be forgiving you. You were ecstatic with glee when you broke the long streak of defeats at his hands and finally sunk your knife into his bones. The red liquid was surprising. You found it funny how much "you are what you eat" applied to him. Maybe it was blood. There was a way to check…

You clench your fists and shake away those thoughts. "sans, if you remember what I did… If anyone remembers what I did, then I hurt them. Don't you feel any pain about what happened?"

"kid, if you can't be happy now…" sans's eyesockets empty for a moment, "then it was all for nothing. the important thing is that it's over. you're not going to reset again, are you?"

"No, everybody's happy now."

sans regains his composure, "what about you?"

"I can't let Chara gain control again. Resetting won't make me happier than I am now."

"ok." sans relaxed. "i don't actually like being sternum with you, you know."

You smile despite yourself.

"heh, there's the frisk i know."

"Are you sure about that, comedian?" You thrust a knife into his chest. However, he slips to the side, sweating.

You're about to swing at him again, but have to dodge out of the way of his summoned blasters. They're easier at first, but he starts to recover.

For a moment, you think you see him frown. He's still grinning, but his eyesockets are empty again and one is glowing blue. You're determined to see him bleed.

You close on him for another attack, but he sidesteps again. You are forced to weave through a long chain of bones to regain your footing. He's not going to use his "special attack" this time, since he obviously remembers. He couldn't conceal his expression when you talked about his pain.

Although, it wasn't you talking about his pain, that was Frisk.

Being determined isn't helping. This is just like before, and you don't feel like dying dozens of times again. His attacks are different from last time, or at least in a different order. You weren't sure if it was a good idea to go after him first, but this just means you can kill the others much more slowly without worrying about another sucker punch from the comedian. At least he isn't talking this time.

Neither are you, though. Frisk is more for conversation, for inspiring those emotions that make these monsters so vulnerable. You allow Frisk's futile struggles for control to succeed.

You take back control with a gasp. You dive out of the way of a bone, but crash right into a chain of blue bones. The energy stings against your skin, "sans, stop!"

sans isn't much for conversation. The lack of an attack from you spurs him to forgo some of his defense in favor of a chain of eight or more attacks by his blasters. It takes all of your energy to avoid the blasts. "Please, sans, I don't want to fight you."

sans summons a long chain of blue bones and sends them at you. His expression doesn't change. You don't move.

"Drop the knife."

Your hand holding the knife is just outside of the blue bones that are moving through you rapidly. You carefully release it. The blue bones dissipate and you sink to your knees.

sans pauses, and summons another blue bone. This one hovers right through your own spine.

"frisk, i can't trust you now," his expression softens, and the glow is gone. His eyesockets remain empty, "i'm sorry."

"I know, and you shouldn't," you say. Would a reset fix this? It hadn't the last dozen times. Every time you think you're making it to the surface, or helping anybody, Chara takes it away. You begin to shake a little.

"careful, frisk." sans stoops down beside you, and takes a look at your injuries. Most of them were after Chara had left you in control.

The comedian begins to bind your wounds. You can't think of anything to say. You grab onto his arm for a moment and look into his eyes.

The malice has left them, and his pupils are back. "frisk, you're still my friend. don't give up now, giving up is my job."

You smile, and whack him in the head with a stick. To anyone other than the fragile skeleton, it would be nothing. In his case, it disrupts all his remaining bones and he gasps. You hit him again and pin him to the ground. You reach over to the side carefully and pick up your knife. His eyes flicker as he tried to fight back.

"Weren't you listening to them?" you chuckle, "Frisk feels everything that I do. And I am not your friend."

He tries to push you off as you press the knife into a thin cut on his skull. He aggravates the movement, creating a pretty jagged line as you slice the knife from the top of his forehead to the bottom of his chin. You don't see any blood, but you sliced him in the ribs last time. His eyesockets empty, and you slap him. The pupils return, he isn't dust yet.

"You know, part of that last fight was Frisk," you admit. Flowey was never this fun an audience, "Every time I fought you, I let Frisk take control a few seconds before you finished us off. Do you feel good about that? I thought you couldn't tell the difference between us, but I thought you should know that every time you killed me, your friend felt the pain."

You cut across his ribs in a wound like last time, but more shallow. "Dozens of times they died to the hands of their best friend. I know it was painful, I didn't switch over to them until about the third death. I don't think there's anything I've done that cuts deeper than that." You pause. Did that count as a pun? You cut across sans's ribs again before laughing just to be sure.

The lovely red liquid bubbles out of him, but he turns to dust before you can do anything with it. Frisk struggles to reset, but they don't have anything you want anymore.

You don't see any reason not to reset, but you should go find his brother and see how he reacts to his brother's dust. You'll kill them all, and then Frisk can reset and you'll kill them all again.