Randomly, Teppei called Konomi "Konomi-chan" in Mebius 9. I remember hearing -chan when I first saw the episode, but since I suck at listening in whatever language, I kind of dismissed it then. I think the script writers either forget that -chan isn't correct, there is some improvisation going on, or there is something in later episodes that I don't remember regarding Konomi & Teppei.
I really, really want Mebius Vs. Tsurugi to last longer. Seriously, I think I could blink a few times and miss it altogether.
(One day I'll get a proper Teppei icon where he is not part of a group.)