It is very rare for vampires to successfully reproduce by biting their victims; rather, the more reliable method is to give birth the same way humans do, which requires a large blood supply for nutrients. Therefore, when humans develop artificial blood, an opportunity to peacefully coexist with vampires emerges. In exchange for contributing to human society, vampires receive sufficient resources to live comfortably and start families.

Seemingly on a whim, a bereaved Raine decides to adopt orphaned vampire child Joel. Raine immediately forgets to purchase artificial blood and uses his own as a substitute. However, he soon learns that feeding vampires fresh human blood has consequences, as Joel begins growing at an abnormally fast rate; within a few months, his adorable little boy matures into a tall and handsome man.

While parenting Joel brings him happiness throughout the day, Raine yearns for a different kind of love to occupy his nights. Unexpectedly, his newly adult son is determined to fill this role as well, proving that he alone occupies Raine's head and heart.