There is no single right way to write a bully romance. A story where a female bully torments a protagonist, only to win her heart with a tearful apology on the last page, is dangerous. It teaches that love is a prize for surviving abuse.
Bull relationships often involve a dynamic where one partner, typically the female lead, finds herself drawn to the male character's strength, confidence, and sometimes, his darker qualities. These relationships can be tumultuous, filled with ups and downs, and may involve themes of unrequited love, forbidden love, or love triangles.