There's actually not much to tell about the series. It's a character-driven 'slowmance' between the short and cute Tsumiki and the kind Io. Everyone around them knows Miniwa is smitten with the popular Io, and he cares deeply for her -- but they keep themselves 'friend-zoned'. Their friends (the loose cannon Mayoi, the cute Hime and the prankster Sakaki) sometimes make fun of them, on which occasions Tsumiki shows that she packs quite a punch in her small frame (which almost always ends up badly for Mayoi).
It's cute, inconsequential fluff. Every episode features two complete stories/situations, so there's enough time to
Another strong point is that the guys are actual characters with actual motivations. They're not just some backdrop for the girls' talk. All five main characters are well-developed, and the supporting characters are distinct and non-generic too.
We enjoyed it, but if you want any sort of action or plot in your anime, you'll be dissapointed by this one. I'll give it a 7,5.