It’s quiet normal to me. If I’m in Kurumi’s situation I’ll also feel jealous or uneasy even if I know they’re just friend. Natural feeling for an unfamiliar face I guess
I think some people misunderstand the reason for Kurumi's jealousy, she's not just jealous because Rio is there with them (although she does seem to regret inviting her to sit down) but because Rio evidently knows a side of Ruriko that she has little to no access to. Ruriko speaks informal with her even though she still calls her own wife "Kurumi-san", she has obviously discussed romance with Rio too, which Ruriko and Kurumi haven't (for obvious reasons, as Ruriko is 100% seriously into Kurumi), etc. So I'd say its less that Kurumi believes Rio is going to snatch away her wife, but rather that she's shocked how a seeming stranger can have so much more intimate knowledge of her wife than she does
Since the beginning, people have been wondering if Youzi is just a good daughter who thinks her mom is gay and wants to support her because it's the right thing to do -- or if she is a baby lesbian herself.
It's still too early for decisive conclusions... but the evidence keeps piling up.
New girl has the wrong idea and thinks that Tae needs to be saved from Mai.
And honestly, all this talk about time/coma/whatever shenanigans is kinda dumb. Like. I'm not gonna lie, it feels like y'all are grasping way too hard for outlandish explanations when the intention's pretty clearly "what if the adult looked like the child and vice versa! how wacky!"