Dear general retarded fen of the Kingdom Hearts fandom,
I have a news flash for you: Riku is not a sex god.
Before the games even start Riku is a confident, and somewhat self absorbed fifteen year old boy. There's room there for him not to be a virgin, but with how gung-ho he and all the other boys where about beating each other up and becoming the best fighter on Destiny Islands.. I doubt there was much time there to really find his groove, along with all the spars, building the play island, and vying for Kairi's/Sora's attention. And if he isn't a virgin, his first time sure as hell wasn't with Sora or Kairi, as that would - just kind of - compound the rivalry between him and Sora for Kairi's affection.
During the first game? Sh'yeah, don't think there was much time there to find a willing partner and hump the night away. Riku was a little busy being jealous, lost, manipulated, and rather hurt by Sora's seeming abandonment of their friendship. Now, you could say that he did rather nefarious things with the shadow Sora, or Kairi's catatonic not-body (Seriously, wtf is that? I don't understand! Unless Namine formed after Sora released Kairi's heart from himself... and that still doesn't make sense.)... Only I highly doubt Riku would rape Kairi; even after he went Mr. Darkity McDark with Ansem, Riku knew enough that he had to stop Ansem and cared enough to tell Kairi, Donald, and Goofy to high-tail it out of there. So, really doubting the theory that Riku could have practiced on her. As for shadow Sora? Who knows what Riku's state of mind was at the time, but he'd see it as being his friend, if not the real version of his friend... And as hot as I may find the idea myself, I really doubt Riku went and boned a Heartless version of Sora.
Then there's the end of KHI, Riku was kind of stuck in Kingdom Hearts with Mickey. As crack-tastic as MickeyRiku is, I highly doubt Mickey would cheat on his wife with Riku because of a minor set-back in his plans. During CoM? Again, Riku was rather busy with righting all his wrongs and learning to cope with himself and what he did under Mickey's caring tutelage.
Even during the year between CoM and KHII still isn't enough time for Riku to become the smooth and suave macho man of manliness that most of you ficcers make him out to be and catch Roxas, embrace the darkness, and infiltrate the Org. XIII. It's not possible.
And you're also ignoring the fact that Riku's somewhat emotionally scarred. Letting your anger, jealousy, and superiority complex get the best of you and nearly kill your friends by potentially ripping their hearts out? Not good for you confidence, as seen near the end of KHII when Riku's about to turn tail and run away from Sora. All during the second game Riku refuses to even let Sora know that he's alive, preferring to work in the background and never meet to face to face.
That says something about Riku's psyche at that point. It says he's insecure, he's terrified of himself, he's feeling an immense amount of guilt and wants to just puff away so Sora and Kairi can be happy (never mind that they both love him dearly), he's terrified of what he might do if Xehanhort's Heartless makes a comeback, and that does not a sex god make.
So, really, all these fics that have Sora/Kairi/Roxas/Namine/Any other cast member/Your SueOC moaning in pure ecstasy the first time she or he hops into bed with him? Or hell, let's not even talk about the smut-fics, just the regular ones, you still make Riku act like he think he's King of the Hill. Riku's not the confident, snotty boy I loved to hate in KHI - stop making him act like it.
Unless you pull it off really well and give some damn good reasons for why, when, and how Riku learned all this, it ain't gonna happen.
And I'm going to laugh at you and then rant about it here. :D
This rant can also be applied to any and all other character in KH where the title 'Sex God' does not quite fit. D: