@rrolo1
Everyone is busy trying to repair the city, no one was paying attention to him. They're not gonna notice someone who at a quick glance doesn't look that different from them. At most they'd just think Youta was a buff woman. They don't have time to actively check him out. And when he was mating with Kia, no one else was there to watch them, it was only the other guardians. As for Kia not being fazed at meeting Youta, the other guardians had already mentioned Youta and that he was a male before they brought him to the city. Not to mention Kia doesn't show emotions, so she's not going to physically freak out when meeting him.
So far nothing that you've mentioned has been a plot hole. We'll have to see what happens after Galia is dealt with and how the rest of the people react to Youta when they don't have a problem currently going on, but for right now you're just trying to nitpick.