Gokukon: Chou Dekiai Yakuza to Keiyaku Kekkon!?

When Hasumi has a chance meeting with her old high school crush, Yamato Kujo, she figures she might as well spend one night in bliss before she deals with the debt collectors that hound her steps. But when Yamato reveals he's become a yakuza member, Hasumi panics and runs away—only to have Yamato pop up again, but this time with a proposition: He'll buy her debt if she becomes his bride. But can she take the pressure and drama of becoming a yakuza wife?

(Source: Kodansha USA)