A mysterious monster called the High Beast, has taken control of the regions of Eurasia and Africa. Japan has cut off from the mainland to protect itself from this threat. The daughter of a legendary mahjong player discovers that monsters attack whenever a mahjong piece is hit across the board. This allows humans to be separated from the battle and for mahjong players to effectively combat the monsters with robots controlled through mahjong moves.

Yuji Mase, a university student who is rather popular with girls without his knowledge, taciturn and withdrawn type. In fact, he hides a secret wound that will be revealed during the visit of his sister hairdresser-stylist: he does not feel at ease in this body of a man that he's in ...

From MangaHelpers:
Minami Eita lives with his older, book-loving brother, whose long-time girlfriend Arumi is often around the house. Minami tries to get along with Arumi, but the truth is that he likes her much more than is appropriate. Even though Minami doesn't read much, he helps in the library with his bookworm classmate Shinonome Yuuko, who loves short stories. She thinks that while most people want to think of themselves as the hero of an epic saga, short stories are much more like their actual lives. Minami's ordinary life becomes more confusing when he begins to suspect that he has feelings for Yuuko. One day, he finds out her secret--she is actually a published author of short stories! Her publisher wants her to write a novel, and she has enlisted Minami's help in an unexpected way. Minami's teenage life is not going to get simpler anytime soon.