awesome story, a couple of spelling errors, but they're few and far between so easily ignored :)
I do hope you continue on with this story as it is interesting and I look forward to hearing storys from the other girls (Considering there are four girls, you have the potential for at least four chapters ^_^)
one suggestion for a (general) plot idea for a chapter would be Tsukasa telling a story that reveals that she's gotten further with a guy that Kagami, this would be particularly amusing since your initial banter implied Kagami has a steady partner in this story.
Keep at this one!!!
a lot of futa but not enough hentai
so please more