>>13411614The joke is that they can handle themselves on their own, and Takeru is more of a child than any of them. Ayamine and Chizuru have an outstanding issue that they can't get over, though they've worked their personalities around it - but it's a problem that's always there and they're not addressing themselves.
Sumika's problem is that she loves Takeru and but he just takes her for granted as a friend, and compared to all the other girls close to him she's one-note because her life revolves around him. Which are both true facts that she recognizes, and because of their interplay, there are no good ways to deal with.
Meiya is the weirdest because her problem is that she wants a proverbial knight in shining armor to save her from the life she feels trapped in (but that she doesn't quite want to escape from, just some self-determination for once). But what she does for that is build Takeru in her heart as said knight, and goes out to find him and do her best to win his affections, falling for him for real in the process.
The only girl that is actually sort of weak is Tama because her problem is lacking confidence (and has big expectations being pushed on her), but she literally just needs a small push and then she's golden.
In all cases, the girls are more mature than Takeru and he himself grows up a little from interacting with them. It's more working out issues together.