Edgar, you damn pedo.

I don't know. Relm was into him and her flirting only seemed to make him uncomfortable.

But aren't Porom's mannerisms polar opposite to Relm's?

Sure, but it's not like she'd actually do anything to encourage him, unlike Relm. She's a sweet, well-mannered, little girl that I think was half Relm's age. Relm had a mouth on her and was quick to threaten people that angered her. She was also passionate about her work, threatening suicide at point when a certain someone refused to let her draw his portrait (although it was a ruse).

Although, Edgar did ask how old Relm was. Maybe he was interested, but didn't want to admit it.

Is there a common term or phrase for "being in the closet" regarding age?

I'm not sure, but for Edgar it was probably him trying to maintain some kind of standard. Lows he would not bring himself down to. Which reminds me, and if I'm not mistaken, the lows to which Edgar would stoop and the standards he claimed to have were a mentioned in conversation moments before Relm was introduced to the rest of the party. Coincidence?

Don't forget that he promised to marry a little girl in his castle "when she was older". Really though, I think he was into boobs and thus was glad to wait for the girls to mature. Otherwise, he probably would have married her anyways.