Chi No Wadachi
It's fucked up, but honestly one of my favorite psychological horror manga out there. Gorgeous art that can range from subtly eerie to intensely disturbing, a family drama that's like a train wreck you can't look away from.... it's great! Also worth checking out the mangaka's other work, Boku wa Mari no Naka.
Kasane
Honestly one of my favorite manga out there. Great art? Check! Homoeroticism? Check. Drama and Intrigue? Check. Complex characters with mixed morals? Check! Augh it's honestly so good. Also, check out the live action movie, it's pretty good too!
Ijimeru Aitsu ga Waruinoka, Ijimerareta Boku ga Waruinoka?
Sadistic Beauty BL Sidestory
Have you ever wondered what it would look like if a bullheaded narcissist was kidnapped by another, even worse narcissist in a hardcore dark confinement yandere story? Well, wonder no more! That's exactly what this story is - one narcissist abusing another into submission. And actually it does a fairly good job at balancing "the victim is an arrogant prick who's hurt and exploited others but clearly doesn't deserve this kind of treatment" and "the abuser is living a life he hates & has nobody he can trust, and he's completely unable to understand the emotions of himself or others, but everything he's doing is still absolutely fucked up and wrong." The art is exquisite, the angst is wonderful, and the writing is by and large better than the original Sadistic Beauty series.
Summer Wars DJ - Donna ni Wabi temo Yurushimasen