UNDERTALE, THE LAST CORRIDOR

You were one of the Monsters of the Underground, being pretty powerful at that, too, but also not really being a Boss Monster like Asgore, Toriel, and Asriel.

But either way, things have been going...very terribly for the Underground. Frisk, the eight human that had fallen down into the Underground, had gone on a rampage, killing every single other Monster in the Undeground.

None of them were able to stop them, even if some managed to kill Frisk, Frisk just came back by reloading their SAVE file without an issue, eventually adapting and killing the ones who had killed them not too long ago.

You were in the Last Corridor. Sans was supposed to be here, but he was killed off start by Frisk before he could even get here. The only Monsters beside you in the Underground left alive were Asgore and Flowey.

Although, you knew Asgore and Flowey wouldn't do anything. Flowey was too much of a coward to even fight back, somehow managing to feel terrified of Frisk despite having no emotions, and Asgore? Well, that you don't fully know...

Either way, you stood there, awaiting Frisk, the true monster here. And eventually...

The noise of slow footsteps approaching rang out in the corridor, as the light shining through the windows in the corridor shined onto the person who had now walked in, revealing it to be none other than Frisk themselves; the Real Knife in hand and The Locket equipped on them to give themselves an absurd amount of DEF.

You were the Underground's last hope. If you manage to make Frisk lose their twisted Determination to keep killing, they won't come back again after you kill them. Good luck.