The only one I particularly like off hand is Matsumoto Rise and Nishigaki Nana from yuru yuri, though Nishigaki claims they're "Explosive Friends" despite Rise's fondness of her, maybe that's how they hide it til Rise moves up since she is a 3rd year student, though they aren't major characters. But Rise actually has more power in it, since she is the student council president and all
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