You could end up accidentally saving a budget version of Toby Turner (or with his permission the real version of toby turner) at the beginning of the game and he becomes your ally ps if you want the ending to be funny you could make everyone think Marzia is going to be your girlfriend but end up with Toby a sequel would be easy with a jealous girl in the mix
A monster version of Marzia could be the villain but at the end of the quest/game/whatever she turns back to normal and it turns out she was helping you all along