Kaiyo is an Omega and an orphan who lived in an Omega Shelter from infancy. Your parents bought him out and transferred him to you as an Omega because they weren't happy that you hadn't acquired one yourself, even though you were already an adult and the successful head of the family business.

Taiyo is a half-human, half-Oni Omega — an orphan who grew up in an Oni village. After the village had some trouble with a spirit demon, which you solved with a one-time-use sacred weapon, the village chief offered you a choice as a thank you: a large sum of gold and one of the village's Omegas of your choice. You chose Taiyo, and he has now been living with you in your home village as your wife two a weeka. (Shujin = Husband)