The Phoenix Sings and the Frost Descends

Loyal Dog! Super Pet! Self-Abasement! Pure Love! Is There Such a Male Protagonist?

I want to read a book similar to "The Big Devil and the Long-Dead Bai Yueguang". The male protagonist is an absolute love brain/female protagonist, absolutely loyal to the heroine, a pure and loyal dog type, he also has low self-esteem and innocent feelings, and feels that he is not worthy of the heroine being so kind to her.