'Stop.'
Waking up, they didn't have a clue. Confused and lost and stuck with them, they didn't know what they were getting into. Several times, several repeated times they wouldn't remember until the end.
Each time, they witnessed the horror again, and again. They could do nothing but stop, and plead.
Dust covering their hands, and the feeling that was felt far too real.
'Please..'
The words began to have no meaning, no matter how hard they tried.
'That comedian...'
Friends.
'Not worth talking to.'
Family.
'Wipe that smile off your face.'
Enemies. No matter who it was, they never wanted any of what happened to happen. They found it sickening, how joyful the child had gotten upon now being able to destroy yet another monster.
Guilt wasn't something that kind of monster knew.
'This potted plant is judging you for your sins.'
Nothing ever convinced them to stop. Nothing ever would stop them.
So many resets had happened, until one day, they finally got bored of the same dialogue. They had finally gone back to their original path.
Now soulless, they did it all again, but they didn't truly care. They didn't care about their friends.
It hurt Chara to see him, their best friend. The one they had to watch... Well, they preferred not to think about that. The ending left them unsatisfied, wishing for a happier one where Asriel was safe.
Not that anyone would be truly safe with 'Frisk' around. You let them have the ending, for now, and watched as they accepted the role of the ambassador and told Toriel they wanted to stay with her. It made them feel a sort of anger.
They didn't deserve this. They didn't even want this to begin with.
Revenge wasn't something they were big on, but in cases like this, they found it better for everyone.