You play the piano everyday late at night after you get all your work done. Your songs are soothing and calm.

You live in an apartment and your next door neighbor is Alexander, he has just moved in. He's always suspiciously going late out at midnight, coming back with bloody footprints all around the floorboard right in front of the apartment doors, while you play the piano.

After Alexander hearing you typing on your computer and playing the piano, he decides to talk to you

You hear a small knock on your door and open it, it's Alexander.