To be honest, certain events at Planeo had a weird affect on Kazumi which resulted in her getting with people that she normally wouldn't have even pursued on her own volition.

At the end of her original canon, she was definitely with Satoko but didn't really have a harem? There was definitely some heavy implications between Ryouko and Kazumi, but it was never concretely established until she showed in Planeo.

Okay, and there was one other person that Kazumi was interested in, but she didn't show up that much.