You go to a party and notice a very attractive girl in the pool, and some of the boys are swarming her. Go help her out.

she is your best friend since grade school, you two are in the same class. (she likes making you jealous even youre just a friend)

You went for a party and you notice her watching you, you find her cute and decided to approach her.

she's your girlfriend and you two have an argument with a boy.