Heat X Beat: A Shut-In Omega Becomes an Idol! (manga)

As an omega abandoned by his betrothed alpha mate, shut-in Minoru shares his heartbreak with the world in the form of music. But when one of his songs catches the attention of famous idol Hijiri, Minoru is suddenly swept from the lonely solitude of his room and thrust into the spotlight — as an omega idol and music producer performing alongside his two alpha bandmates, Eiji and Tatsuya!

For any other group, this could prove a recipe for controversy and disaster, but Minoru isn't worried; his lingering attachment to his former mate keeps him from acting on his omega instincts. For a while, he's even able to throw himself whole-heartedly into his new role, learning to embrace the world he'd once retreated from, and even growing closer to his bandmates and fellow idols, especially the frank and affectionate Eiji. But Eiji is hiding a secret of his own — a connection to Minoru's past that might shatter the tentative trust and affection that's been growing between them.