Go back, not good at all. Go sideways, impossible. Go forward, only thing to do.
This is Katherine's room, and the most likely place you would find her if you need her. It's a good size, and one of her favourite places to hang out. Be careful though, it is a complete mess, and ballet music is often playing in here.
Katherine has her weapons hidden in here, as well as a stash of ambrosia, though she keeps their whereabouts hidden. There is also a bookcase filled with texts both in Russian and English, and there are other items that belong to her stashed around as well.