I wonder why, I wonder how

I don't know what <3 really is? I saw a girl, never talk really much as in chatting, looks a little pretty than normal, yet I keep thinking of her every single day. Whenever she is around me or I see her in somewhere, she doesn't really excite me, but when she's 'vanished', then only the feel comes. AND I just realized that I started to care who is going after her. Could a guy and a girl be a really good friend without prejudis by the public. A good friend here is not meaning the relationship, is the person could support you, could give you a hug, protect you, even give you a kiss on cheeks.