Forbidden Love Yaoi

Biological brothers
Brothers separated after their parents divorce reunite in a school dorm and fall in love.

Biological brothers
Brothers Yusuke and Tokio find run into each other in the city and learn the other's secret, Yusuke is gay and Tokio is bi. Yusuke wants to talk it out and be a good big brother, but Tokio can't see him the same way anymore (because he sees him sexually).

Biological brothers
Chihiro spoils his manga artist little brother Chikage, and when Chikage asks to sleep with him, he assumes it's for a manga.

Biological brothers
Kanata feels the stress of being an older brother to his brother Ketia, so he destresses by getting spoiled by men at his job working as a "little brother" in a themed sex shop. When Keita finds out about it, it prompts the two brothers to reconcile, become friends again, and then become more.
Trigger warnings: sex work, attempted rape, incest(brothers).

Biological brothers
Little brother obsessed with older brother, older brother aware and totally mocks him but sometimes goes along with it.

Biological brothers
Older brother becomes a prostitute to take care of younger brother, younger brother feels a sick sense of superiority about it.

Biological brothers.
Little brother accidentally hits his brother with an aphrodisiac that doesn't work, but the older brother pretends it does and uses it as an excuse to get down and dirty.

Biological brothers
Haru confessed to his brother Aki 5 years ago, but Aki brushed it off. Since then Haru hasn't grown because of his pent up feelings, so when he does grow all at once, he's ready to make Aki believe him.
Trigger warning: incest(brothers).

Biological brothers. Cousins.
Younger brother gets older brother drunk to have his way with him, and everyone else gets up in the mix.

Biological brothers, twins
Azuma is in love with his twin brother Miyabi, who is great at archery and bad at everything else. Azuma does everything for him and eventually starts taking advantage of him in his sleep, but when Miyabi finds out he's very chill about it.
Trigger warnings: rape(somnophilia), incest(brothers).