Okay, They should have just done part3 and not bothered with the two previous parts. Yes okay, we get the whole tired old "friend has sex with female turned friend" thing... while it is better than random rape and mindbreak ect, it has always been a bit too sugary sweet for my taste and it pretty much always has the genderswap go OOC and become all feminized.
So, the whole sex in this one was a bit out of the blue -- but the comments alone made up for it. Like such classics as:
1. Seiya being gay XD (wait wut?) 2. Seiya thinking its okay to have sex with a girl since that girl is a guy he likes. 3. Seryuu instead of thinking this means that Seiya is in love with him, thinks this just makes Seiya a slut.