Very hardcore/graphic yaoi including incest, bondage, piercing and toys.
Brothers involved in sexual relationship involving hardcore bondage. 3rd guy gets involved with uke. Lots and lots of graphic sex.
Includes one shot "Platonic Lust".
(from M-U)

Takumi is an orphan who just moved into an all boys dorm. He's rooming with his childhood friend, Hikaru and meets up with his childhood sweetheart, Hikaru's twin Kodama. But the twins keep switching on him! Who is he really in love with?
(from B-U)

1) Fevered Glance or Heated Look (Netsu Shisen)
High school playboy Tsuji can't understand why his best friend Mitsuse turns down girl after girl. When Mitsuse admits to having a crush on a male classmate, Tsuji is floored. Will he ever be able to look at his friend the same way again?

2) Piercing the Heart With a Kiss
Continuation of one.

3) XY - Let's Go to the Festival (XY~Omatsuri de ikou)
Extra of the story XY. Takaya loves chocolate bananas and his friend Nagisa, so combining them...

4) Shy Us (Uchiki na Bokura)
A perverted teacher preys on his junior high students, but is he really the one controlling things?

5) That's Why We Fall in Love (Dakara Bokura wa Koi wo Suru)
The perverted sensei from "Shy Us" is back, but he's not touching the one person he should be.

6-8) The Town in Which Good Children Live (Yoiko no Sumu Machi)
A perverted shopkeeper deals with a shoplifter, a selfish dog owner, and a thief in his own unique ways.

Takeru’s mother is about to remarry. That is a great opportunity for Takeru to live with a real family and, most of all, to have a big brother, Shin. Things do not actually turn out the way he expected, though.

One day, while waiting for his girlfriend, Takeru hears a couple of people discussing about money for sexual favours. Curious, he turns around to check out the chick, but it turns that both parties are male. However, what shocks Takeru more is when he realizes that the one prostituting himself is Shin, his new stepbrother…

First volume extra : Shounen S.

There's also a book of various doujinshi called Renai Junkie. The fifth story is a spinoff of Aitsu to Ore called Newly-Wed

From Tokyopop:
Kaito Yagami is a florist/gardener by day and a hired assassin by night. He kills using plants to make money to care for his brother who is confined in a hospital.

Four-eyed Natsui is ignored by everyone at school or they highly suspect he's an anime dork. Little does he know, sexy Ritsu has been staring at him from afar. What happens when the glasses come off and what's next... the pants?

NOTE : Sequel THUNDERBOLT BOYS: EXCITE