
I can understand where Momo is coming from. She’s only had her brother all her life, and the mother is probably almost always absent. It’s just the two of them.
So her being overly jealous and protective of Umehiko, as immature and annoying as it seems, just makes more sense, because now her only family is being ‘taken away’ by Theo.
Hopefully Umehiko makes his boundaries clear and talk to her about it. She’s already 15, she can handle a conversation.
Also, I dropped this months ago bc of how it started, but there’s actually interesting plot going on after reading it again ironically.