I'm Sorry, Masumi-kun!

Shotaro Shiraishi is an author. His daughter, Risaki, was supposed to marry his editor, Masumi. The two were supposed to live with him, but when Shotaro's daughter disappears on the day of the wedding with only a quick apology, Shotaro and Masumi are left behind. Desires go wild as the two men begin living together in this romance between a son- and father-in-law!

(Source: Renta!)