The episode uses Suu’s arrival to highlight Miia’s insecurities. She isn’t just jealous of another girl being in the house; she is worried about losing her "Darling." The cold temperature subplot—where Miia becomes lethargic due to the weather—adds a layer of vulnerability to her character. It reminds the audience that despite the fan-service and comedy, these girls have biological needs that make living in a human world difficult.
The climax of Episode 2 involves a trip to the grocery store. Agent Smith orders Kimihito to take Miia into public to “normalize” her presence. This goes horribly wrong. monster musume no iru nichijou episode 2
Yes, two.