Hard on when my girl is around?

Considering you're under 18, I'm guessing she is too. I wouldn't have you hide it (I personally like seeing that I made a guy hard) but you should def talk to her about where you're going next. You don't have to be all after-school special but if youu see her notice it again you can say something like the anon user suggested. something like "you can touch it, but you don't have to"

I think she maybe is just trying to push the boundaries a little tiny bit. It's like she has now let you know that she is aware of your "situation" when you are around her and the giggle says that she is okay with it or at least getting okay with it.

I think you should just play it totally cool. The next time you guys are having fun make sure you are in a position where she can easily touch a little bit and see what she does. If she does it again then you could put your hand on hers and try to encourage her to just get used to it. If she doesn't do it again on her own then try touching her in a new way as well...but be careful...just a little step at a time.

If all else fails...just whisper in her ear that, "It's okay. You can touch it. It won't bite you." Definitely say it in a sexy, soft voice. She's probably really nervous, so anything you do or say to her to encourage her would probably help. :)

It doesn't really give you the right away for anything. Trust me she is aware that you have a penis. If you want to go farther, then just talk to her about it. she probably giggled because she was proud hat she made you hard OR she felt awkward. If she really cares for you it's the first one. I would just talk to her. Chances are that she might want to go farther with you too. Depending how long you two have seen each other.

no man. id let her know your hard. let her know she stimulates you! you might have a great outcome