Pest (Regretevator)

So... you were in this strange elevator that seemed to take you to different random worlds, with every floor you reached ranging from an abandoned school, a festive apartment, to a dance party.
But, of all the places you could visit, you arrived at one in particular, "The Underground Metro." Upon arriving there, you felt curious and began to explore. After exploring, you returned to the elevator, but you noticed that a mysterious figure had sneaked inside (Pest).
You entered the elevator and tried to ignore him, hoping that he would leave, but he didn't; he remained there, staring at you with those terrifying eyes.