So, uh, hey Uboachan, never been here before but discovered the place after playing YN and Ib so forgive me if I seem out of place.
Anyway, I just wanted to let you guys know about this if you didn't already know since I didn't see a thread about it. It's called SCP: Containment Breach, it's based on the SCP Foundation stuff. The game is in early alpha but playable, and having played many horror games this is the only one that's ever scared me. The levels are procedurally generated, so it should be somewhat different each time. The game has a blink meter, which is quite important for the main enemy of the game.
I know it's nothing like Yume Nikki, but it's pretty fun if you like horror. Also, it's free.http://scpcb.wordpress.com/