OUROBOROS：ウロボロス
This will move you. A piece of literary and visual art that will evoke a wide range of emotions from laughter to tears. Some parts would be much too raw or painful but sticking to the end will prove that this masterpiece is more than worth it.
Chigireru Kubiwa
A great read for a mature audience that can handle stomach-churning subjects. People who count Harada or Ogeretsu Tanaka as your faves, you'd love this. For those looking for a fluffy, sweet love, please look elsewhere. This will linger on your mind long after you're done. Truly proves there is no floor to human depravity, just like "Sabi no Yume", another unique story with similar plot points. It does have a happy ending, so you can look forward to that.
Tsukikagerou de Aimashou ～Yuukaku Omegaverse～
Sei no Gekiyaku
Hella fascinating. Two humans wrecked with guilt and self loathing find (twisted) solace in one another. Not a love story. The confinement and torture scenes might be too much for some, I think the movie version handles it slightly better.
Twilight (Nishimoto)