Aigan Shounen
A dark but good smutty story, with some harcore BL elements.
Kimochi no Yukue (MEIJI Kanako)
it's okay, with his TKS this manga had much more to work with, but it didn't do a good job explaining their relationship, or the issues themselves.
Ochiru Seija no Seppun
3 short stories about slave/master relationships in a school. Definitely hardcore, lots of extremes and mostly uncensored. A good hardcore manga, just be prepared for s/m.
Nightmare Fortress
Definitely read this for the sexiness. We have semes, ukes, and more switches than any manga I've read! A fantasy world with benevolent ruler of a small island paradise, suddenly gets invaded by demons searching for an artifact. These demons don't kill, but take over the mind by having sex with all the humans and making their bodies fall in love with sex. In his last act of power, the prince saves two of his guards and separates their island from the real world, and they try to get back to their island to save their prince by becoming indifferent to the demons sex magic, by having sex! Uncensored, hardcore sex everywhere, done in a pretty and sexy way, but be warned, the plot is designed for the sex...lots of fun smut
Mob For Jack