There's far too little information to really say anything authoritative (like we don't know his age or personality) but here are some possibilities:
1) Awkward - he's actually exploring the idea of coming on to you or taking your friendship to a romantic level but did it in a "typically stupid young male way" that would chase off anyone with a clue. Seriously, boasting about "lots of sex" (true or not) is a turn off for almost anyone. If anything, the next question is "what is he infected with?"
2) Did his revelation come out of the blue or was it in context? Were ya'll discussing the idea of dating protocols, for example? Usually, this sort of weird moment is the top layer of a lot of other bubbling issues (possibly unrelated to your relationship with him).
Take any posts you get with a grain of salt (including mine) ... you're asking the hordes of possibly unqualified
