Who? Drew Barrymore as Ivy

Symptoms: Moving into your house, sleeping with your dad, murdering your mum, that kind of thing. And as an extra treat, while she's driving, you ask her about your mother's 'suicide' and she crashes the car, Vanilla Sky style, but also moves your unconscious body so it looks like you were driving. Evil and genius, what a brilliant mix.

Ron's Lessons In Love: Our top tip for Ron in this situation would be not to let insane women move in with you, under any circumstances, ever. Write that down in your copybooks now.