Trans rep in wonder egg!

Did anyone see episode ten of wonder egg priority? They had a trans boy. His name was Kaoru. I was a little confused as to how that could happen, because beforehand they said that only girls could be in the wonder eggs. So I don't know if that means, that they were wrong, they were lying, or (the less preferable option) he still counts as a girl. I hope they actually explain that, but the episode was really good, the character had a pretty sad backstory, but he wasn't all mopey or anything, he was fun and charismatic and flirted with Momoe in a perfectly masculine way. I think he was a really good trans character, I'm really happy because I don't see a lot of ftm characters, let alone well written ones.
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