I like to think that that part of Mami's sidestory was before Rika met Ren. Otherwise, Mami might need to be careful of a certain scythe-wielding magical girl the next time she's alone in Kamihama.
You know, I always felt like there was something between the two side character girls (glasses girl's friends) in Takagi-san. This makes it seem almost plausible that I wasn't imagining things...
I happened to walk by a live Locodol performance while I was in Japan. It was pretty surreal... but I couldn't help but think of these two characters. Nice to see more of them.