Oh, I don't think he was that clueless. At least given how flustered he was in Accent Core after that line Dizzy gave him.
He wasn't, through if you asked Johnny at the time... half the reason that Johnny was ok with Ky being around Dizzy stems for the fact that he through of Ky as way too much of a prude to try and get any. Proved him dead wrong about that.
Eeeeh, not so much that Ky was a prude as that he wouldn't, y'know, force anything with Dizzy.
Admittedly neither would anyone who knew about Necro, but still.
Ram?It hurts!? Are you okay!? And wait, your face is all red... Are you sick!?What's up? I said you could smile whenever you're happy, didn't I?I'm happy... but,My chest hurts so much, my face won't move.I don't think so.I can really sense Ky-san's blood in him.Poor Ramlethal-san...Eh?Why?Did I do something wrong!?Mmmm?