hmm well, it depends what u mean by underage, because i dunno bout us but in the uk the legal age for sex is 16, so if its like the night before your 16th birthday then your underage, i dont see it as that.. at the age i am now i wont touch anyone more than 3 years younger than me, when i was like 15 then 14 or 15 year olds were fine....

... and theres something else, incest is considered a great taboo also but what are the boundaries? is having sex with say your step sister incest? because she isnt your relation by blood but by marraige