@johnpoop2529 Imagine thinking that the type of genitalia you have dictates the type of clothing it's natural for you to wear, and that straying from that type of clothing is unnatural and not true to who you are.
It's called crossdressing because it's one gender wearing clothes that aren't commonly used by them in our current society. Fashion trends change all the damn time, saying one type of clothing is male and another female and that straying from those norms is not being true to yourself is dumb as all fuck. Nothing "PC" about it, it's just not letting your 'true self' be dictated by the whims of fashion like some sort of sheep.
Also, yes, he gets embarrassed about it, but he was clearly into it and exited about it in the very first chapter before he had even met Hazuki.
People can be embarrassed about things they enjoy if they think others will view them strangely because of it. It takes time to learn to not care what others think about you. Iori is only 19, he's most likely far from that point in his life.