Tichoronda
First off, it sounds like he has issues, like parental stuff; and to boot he continued...?
The " I promise I'll never do it again " doesn't cut it, as a kid this happened to my mom a lot, and it always ended with that sentence, next time he does it; it'd bash the guy in the sack and call the cops. I don't care who the kid is, that's not cool, I'd kick his a** myself, but of course this is the internet, so that's a negative; unless he happens to live in CT, XD.
Anyways, I'd let it go, and what-ever you do, don't be afraid of him, that only promotes it, if he ever, and I mean ever even comes close to that again I'd do something. How old are you and said guy?
he is 14 and i'm 13, 14 by the end of this month, he is the sweetest guy, i wouldn't have expected that from him, that what scared me