Yen Ragun, who tries very hard to be the smartest boy in the entire district, is constantly tied with Ayato Housui. He comes home from school one day to find that Ayato is his cousin and will be living with his family indefinitely. But he doesn't have time to worry about that, because he and his little brother Jin are constantly undergoing training to join the family business as Gakushi. Gakushi are people who take care of ghosts, evil spirits, etc. all referred to as Maga. For their training, Yen and Jin get orders from their father and must solve clues in order to complete their mission. . .

Yen Ragun
The eldest boy in the Ragun family, sixth grade. Yen, who loves to study, has ranked the highest on the national elementary school standardized tests for five years running! He has read and memorized all of the many Gakushi reference books in the Ragun home and takes things seriously, always thinking of his younger brother. As the eldest son of the Ragun family, Yen has a strong sense of responsibility. Although Yen take things seriously, he also has an energetic side that is a match for the mischievous Jin, and a calm side that acts logically. In battles with Maga, he spreads barriers and analyzes the enemy. While he's at it, he keeps Jin under control.

Ayato Housui
Yen and Jin's cousin, who is staying with the Raguns. Ayato is a sixth-grader who has tied with Yen for first place on the national elementary school standardized tests. He's the president of the elementary grades at Koujin Academy, and is at least as much of an honor student as Yen! A kind, quiet boy, whose somewhat-lonely eyes are another one of his charms. He's not a "Gakushi," but he's someone who understands the brothers and is there for them to rely on.

Jin Ragun
The second son in the Ragun family, fifth grade. He'd rather exercise than study, and is the type who reacts before he thinks. He's mischievous and quick to fight, and shows no mercy. He's even childish with the ladies. Jin's a spoiled boy who takes advantage of the fact that his brother is always willing to help. To put it bluntly, he has a weird brother complex. Jin does have an adorable side where he will stretch himself to the breaking point for Yen (and there's also the danger of him going berserk for his brother). In battles with Maga, he's in charge of the attack.

Hideaki Ragun
The current head of the Ragun family, who goes out for work dressed as a normal businessman, with a suit and tie, but is actually a Gakushi. He's a wonderful father who gently, yet sternly, advises his inexperienced sons.

Akane Ragun
Yen and Jin's mother and a popular novelist (pen name Akane Mari). She is also Ayato's mother's older sister. She's a pretty lousy good cook with a somewhat abrasive personality, but she loves her children more than anything.

Erei Moribayashi
Yen and Jin's childhood friend, who's in the same grade as Jin. She comes to get the boys every morning, and they walk to school together. She's cheerful and competitive, and she always quarrels with Jin. She's quick to fall in love, passionate, and loves all those pretty boys!

Shintaro Nagasaku
Yen and Jin's mother's editor. He's twenty-eight, single, and looking for a significant other. He's a strange editor, who has naturally melted into the Ragun household. He likes to cross-dress, and speaks a little like a girl, but he's a good person, and will cook meals when Akane is busy.

Yukiru Sugisaki
Yukiru Sugisaki was born on December 26, a Capricorn with blood type O. Her hobbies are dramas, video games, and 'collecting rabbit things.' She made her debut in Asuka Magazine with Namaiki no N.Her other works include DNAngel, Rizelmine, and Lagoon Engine (her newest manga).

Sugisaki-san is also the artist of the BrainPowered and Candidate for Goddess mangas, both of which have been animated. Her Neutral artbook contains artwork from DNAngel, BrainPowerd, and Candidate for Goddess. She has also penned the well-known Sotsugyo M.