Excellent, lets see if my plan is coherent enough since I'm sleepy as hell.

Lets see, it revolves around lots of apoligizing, guilt, and feeling like utter shit... That's mainly for Kami because stuff happens when you are a sort of panicky coward character.

Sachiko -> Kato or Ayano but most likely Ayano then Kato.

If you like, I could try and figure out a way to connect all four stories if you guys like.

Edit: I was going to have Kami be in the same year as Akemi when I saw her post. It might or might of not been because I wanted to cause interesting story tension between Kami and Midori :P