Transmigrate and End up with the Gentle Second Male Lead or Supporting Male Character

Looking for historical or cultivation stories where the protagonist transmigrates or transmigrates into a book and ends up with a gentle second male lead or male supporting character. A sweet-on-the-outside, dark-on-the-inside type is fine. Basically, I want a male lead who's gentle and refined on the surface, but can be goofy, scheming, or a little possessive in private. BG only. No rebirth, no contemporary settings, and no BL.