This term has been remarkable lately because of this same title shoujo manga, オトメン. So it is a kind of clarification for men, which simply means young guys who like BL stuff or otome games even if they’re not gay. If you have this manga, you already saw the definitions for オトメン on the back cover(or else, it’s told in the story).
1. Young men who likes BL stuff or any other otome things.
2. Young men who are good at any chores.
3. Young men who are actually feminine whereas they are so manly in front of others.
In fact, in this manga, the first definition is not mentioned, but I think it should be. Having said that, this might be controvertial because even if he loves shoujo manga, that wouldn’t necessarily mean he is a BL fan. Such guys are maybe 腐男子([fudanshi]; male version of 腐女子[fujoshi]).
Me? Well, a certain friend of mine made me admit I am an オトメ I have played some otome games and like them, and I am not bad at any chores…so umm, yes, I am the one. orz W-What? What’s wrong with being オトメン? I think the era of オトメン will be coming soon for sure!