Baron

バロン
From Viz:
http://www.mangaupdates.com/series.html?id=4550

When awkward schoolgirl Haru rescues a cat on her way home from school one day, the last thing she expects in return is to be honored by a feline royal family! Before she knows what's happening to her, Haru is drawn into a world inhabited entirely by talking cats--and recruited to be the next Cat Princess! Only the dapper cat Baron and his friends, a magical crow and a comical fat cat, along with a friend from Haru's past, can help her return home.

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