Haiiro to Aka

Yuki Tachibana, a second-year high school student, has been living life in grayscale. No one has been watching him, he has only been breathing in a colorless world. Only Hotta, a delinquent, has found Tachibana. "From now on, you're my slave," Hotta declares. He's violent and sharp-tongued, yet Tachibana knows that whenever he's with Hotta, color bleeds into his world. He savored the pain Hotta inflicted, but his true desire lay elsewhere.

(Source: Taiyo Tosho, translated)