CAELOPHILE

The male lead (ML) acts very cool at the start, leading us to believe he's seeking epic revenge for his sister and that he'll play along with them. But no, the ML is weak! The number of times he offers his help to the female lead (FL), only to be refused every time, is unnecessary, especially since it's usually the secondary couple that helps everyone.

As for the romance, it was lackluster. I don't understand when or why the FL gives in to the ML; he's just so unlikable.