It is about 18-year old Ordinary High-School Student Shinji Jyoushima and his very perverted 16-year old sister, Kanami. Like many 4komas, it is a Slice of Life comedy, dealing with the daily life of the siblings. Its humor is mostly of the sexual kind, mostly delivered by Kanami, who often has nothing else on her mind than sex (although she isn't the only one who seems like that).
This manga provides examples of:
- Fanservice: Surprisingly sparse, considering that it mainly deals with sexual themes.
- Goldfish Scooping Game: While playing the game, Manaka gets quite a few fish and attributes it to her scoop not breaking because she is still a virgin.
- Parlor Games: Kanami starts a shiritori game with her kindergarten class and their teacher starts to say reezun (raisin) but then she realises that means she would lose and changes it mid-word to rezubian (lesbian). The other teacher is shocked, but Kanami just cheerfully points out that she loses.
- Porn Stash: Shinji has one, but — much to his chagrin — Kanami likes to take magazines without asking.
- Running Gag: Kanami's classmate Kanou Miho, who has a crush on Shinji, attempts to get closer to him — and is always foiled by Kanami.
- Troubling Unchildlike Behavior: Even as a kindergartner, Kanami already had a dirty mind. Of course, it is Played for Laughs here.
- You're Drinking Breast Milk: Implied source of the milk Komiyama-sensei digs up for the teacher's lounger.