Here is some regular info for you:
Age rating: Teenagers (May contain bloody violence, bad language, nudity).
Genres: Adventure, Comedy, Fantasy, Shounen.
Synopsis: At Daimon High School, kids settle their disputes by dueling with each other in the school's official K-Fight battle arena. Ryoko Mitsurugi, samurai girl and undefeated K-Fight champion, is called upon by a mysterious Priestess to protect the Earth from an invasion coming from the alternate universe of Solvania. She must face battles that will test her skills, her friendships, and her heart in order to find her true strength as a samurai warrior.
I read the first volume and I found it pretty amusing. As for little sister, who is huge fan of Samurai Girl, loves the manga to the core. I think she has read up to volume #5. She tells me that it is one of the best that she has read.