Aya thinks Suiren is fine as she is. I guess that shows that Aya is fine with being her bodyguard or perhaps, she might lose her purpose if Suiren becomes strong. There is also, she likes and accepts Suiren as she is, why change. But then, Suiren has to change for she doesn’t want to cause hassle/trouble to her and Kawasumi. She doesn’t want Aya to always play bodyguard with her. She wants to be able to easily deal with the guys who aren’t exactly the type that she can handle. As the boyfriend, I guess Kawasumi is a bit jealous and helpless that Suiren is asking another guy’s help on this. It is nice that Suiren mentioned it to him so that there would be no misunderstanding. It is also nice to see that Kawasumi is becoming more proactive and even mentioned the anniversary. That is something to look forward to and there’s the kiss. In the end, it seems that Atohira didn’t teach Suiren much but just to hint on treating the others the same.