Mr. Flower Bride(2004)

Hanayome-kun

Shinji Souda’s not exactly happy about his family’s age-old marriage customs, namely the fact that he has to marry a boy! Will a sudden confession from his bride-to-be, a beautiful boy in his class named Aoi, make Shinji change his mind? This sweet love story follows the couple through their marriage ceremony, wedding night, life as newlyweds, and even childbirth!

(Source: Yen Press)