Ashigei Shōjo Komurasan!

From the introduction: Some stories are about incredible worlds. Some stories are about incredible people. Some stories are about regular people, in regular worlds, with very… irregular habits. Komurai Komura is a sweet and athletic girl, who just happens to descend from a long line of acrobats who passed down many eccentric traditions. Namely, from the day they are born, they train themselves to use their feet for absolutely all tasks. Really, the only role their arms serve is to support their weight during hand-stands. The result of this is an almost superhuman flexibility, balance, and overall athleticism.