I Fed Three Beast Kings, Then Broke Them

After three Beast Kings betray witch Olivia Parker for Anita, a scheming fox, she turns to Gabriel, the Merfolk King, for a new life. With his help, she uncovers Anita's murder of her father and takes revenge. As the three kings lose control of their beasts and beg for forgiveness, Olivia rejects them and becomes Queen of the Deep Sea.