go for it - there's nothing illegal about dating a 15yr old, just don't fuck her

you're keen, she's keen - why not

my Dad met my mom when he was 20, and she was 15 - big deal huh
they married couple years after

you're not breaking the law, you can stick your fingers in, but not yer willy - bonus, she can sucky sucky

to sum up

GO FOR IT, YOU'VE NOTHING TO LOSE AND EVERYTHING TO GAIN