Come to think of it; Harumin looks like Yoshino with her hair down XD
Haha yeah, and also with the whole possibility of calling Yuzu "onee-sama/onee-chan," with Mei looking a lot like Sachiko (even acting like her sometimes) and the fact that both them are attending an all-girls school, I can totally see the similarities. lol
Really though, most yuri storylines I've seen/read have at least minor references to MariMite. They're, like, paying homage to the manga! I'm fine with it, though, just as long as they keep it to a minimum.