It certainly seems to me that Kaho isn't letting on that she is also looking for love. If not like a plural system, at the least the girl has issues that i don't think she addressed yet. It's very clear that Kaho has a crush on Renako and can be herself, but she does have relations with everyone in the would be polycule. I think her main arc is going to really close the book on the series by showing that she also has a massive inferiority complex mixed with family issues that she hasn't talked about yet. Something like how her father may be a politician or he married for material gain and kinda instilled that in her as well. Like he loved her mom, but they didn't last because of other issues or something like that. Mixed with her known inferiority I can see her splitting herself off the whole poly group once Satsuki joins because she will feel left out. Like a sort of mix of what Renako went through to realize she has self worth and all her relationships made her a better person, I think she would do that for Kaho and it make for a nice sorta round about way.