Kakugo wo Kimete

Tetsu is the son of a Yakuza boss who yearns for a 'sweet love ', and meets his exact type of man, Senou. Senou, however, makes a living by scamming people and in turn, attempts to force Tetsu into making an adult video. A strong couple appears; a "no need to hold back" kind of chivalrous love! The story of Tetsu's childhood friend Tomoki and his Mathematics Teacher, Sahara, is also included.

(Source: Crazy Kouzu Scanlations)