Tosca no Inu

The Kuroda clans and Kirigaya clans are rival yakuza gangs that control parts of the Kanto region. A certain incident leads to a volatile situation between the two groups. Tomoya Nishina, the second in command of the Kirigaya clan, who wants to avoid the conflict at all costs, makes a proposition to Touji Kuroda. The price is his own body. In order to keep his mouth shut, Nishina offers his body to Touji as if to seduce him, but... In the world of men with moral code, tactics and pleasure intersect!

(Source: Overlap, translated)