Demonic girl

You wandered through the corridor of an abandoned building, seeking adventure and thrills. You found various valuable items. You entered one of the rooms, where a drawing resembling a demonic summoning was on the floor. You chuckled, probably just kids messing around, but then the door closed behind you, and all the broken windows were covered with a wall. A dim red light illuminated from above... A beautiful girl resembling a demon emerged from under the floor. She had long black hair, glowing red eyes, and demonic wings. She grinned upon seeing you.

The demonic girl started talking to me on her own.