Furenaide Little Star

Yuki and Haru are father and son... well, not exactly blood-related, but they are family. Yuki is a single omega who works as a designer and raised Haru, who later turned out to be alpha all by himself after their parents died in the same car crash years ago. Everything is fine between them until Haru turns 18 when he kisses Yuki and confesses his long-time feelings for him. Their familial relationship is suddenly thrown out of whack. To make matters worse, Yuki's long dormant omega nature suddenly makes itself known, leaving certain complications in their already strained relationship.

(Source: Fantasista Inc.)