First Call: Doutei Gekai, Toshishita Yazuka no Yome ni Saresoudesu!

Sota is a young ace plastic surgeon at the university hospital. One night, a man with a full-body tattoo and a pierced penis is rushed to the hospital after a traffic accident. The man is Seiichiro Ibu, a yakuza gang boss who controls the whole Kanto region! Ibu survives, but falls in love with Sota at first sight. Ibu chases Sota around the hospital in his wheelchair, and proposes to him with a bouquet of roses accompanied by violins! Will Sota Takara, a 32-year-old virgin doctor, really get married to a younger yakuza man?

(Source: Eclair Novels, translated)