1) the consequences to the boy (note that this does not hold for gilrs) is not a severe as you are stating, and there is strong psychological evidence for that. The most damaging thing is if he views the sex as abuse. Most men who were "molested" as boys (something in the 80% range in a very large study) viewed it as a positive experience and that it had no negative effects in their lives, and their rate of success was normal.
more importantly though
2)We cannot change our orientation. My orientation is primarily towards 12yo boys, and there is nothing I can do about that. Psychologists have tried for decades and have decided that it is not only impossible, but hurts all involved to try (with the exception of permanent chemical or physical castration, but even that doesn't actually change the person's orientation, just stops their sex drive). Yes, God could change me if He wanted to, but He has not despite my asking and pleading and trying and begging and screaming and crying. I cannot cnage myself, and God wiil not (so far) and so instead I must find a way to live with this desire and ues it to do good in God's world. I don't know how yet, but God and I are working on it, and we'll get there in due time.

Love in Christ,