Klaus is no stranger to writing on walls, his own are full of plenty of things-- some from ghosts, that he let himself almost do a form of automatic writing for; others of the words on his walls are his own, but he'll never tell which was which. Nobody needed to know.

Five's room looks distinctly... different than he remembers. They never changed it, or threw anything out, after he left. It seemed wrong to do, and Vanya probably would've pitched a fit about it anyway. As he's taking in the differences that he can note in the darkness, he misses the chalk on the floor and steps on a piece just so in the right way to make it catch and roll under his foot and send him off-balance and on his ass. Way louder than he was trying to be, which means it's just the most natural end this moment could have met. Everything is always louder when you're trying your hardest to be quiet.

"Ow..." he mutters, rubbing a spot on the back of his head where he'd hit the ground.