N's room is meant to be a metaphor for what his mind was like before and after he was told that he was being manipulated. In bw his room is very innocent and naieve, just like N. However this entire image gets warped into something more fucked up when the castle crashes, in other words his room is destroyed, just like how his naivety and innocence was. The reason why he leaves is probably because he cant emotionally handle it, and I don't blame him, trauma is one hell of a bitch to get over.
Also N theme is literally called "Prisoner of a formula" which is also saddening, now that formula is broken, but the prisoner is compromised for life.
good ending: black and white 2 never came out so u stay with this music bad ending: they deleted black and white 1 so u had to listen to death kids song
