Angel might be an heir, but she sounds more like a red herring to me. She genuinely seems not to know who MC is when they first met, yet she might have been pretending. But then, when they are fooling in the back room, why would she mention her bossy ex? If she is scheming behind the back of MC, the less he can connect her to his father, the better is for her. And then, MC suspects his father, when he hear of her older bossy ex. That makes me think of a red herring.
And i kinda suspect that CheekyGimp might be taking notes about our speculation for the future twists