All are Rentaro's girlfriends. They are close to each other and have no jealousy.

Hanazono Hakari - Female, Age 15 (1st year HS). Pervert, Rentaro's 1st girlfriend, Hahari's daughter, Karane's friend. Gag character 1.

Inda Karane - Female, Age 15 (1st year HS). Tsundere with incredible physical strength. Rentaro's 2nd girlfriend, Hakari's friend.

Yoshimoto Shizuka - Female, Age 15 (1st year HS). Quiet and timid. Rentaro's 3rd girlfriend. Cute + weakest (but receives lots of love). Library club.

Eiai Nano - Female, Age 15 (1st year HS). Efficiencyist, top of the school. Rentaro's 4th girlfriend. Often looks after Shizuka. Speech style: "When there is something you want to do, it is more efficient to act than to follow procedures." Speaks like an AI and calls others by their full names.

Yakuzen Kusuri - Female, HS Senior. Chemistry club, makes many strange drugs (causes chaos with them). Rentaro's 5th girlfriend. Has an 8-year-old body due to an immortality drug. Ends sentences with "~nanoda" (it is). Gag character 2.

Hanazono Hahari - Female, Age 29. Rentaro's 6th girlfriend. School chairwoman, wealthy, Hakari's mother, pervert. Gets nosebleeds when seeing cute things. Close with everyone. Can be serious but usually isn't. Gag character 3.

Haraga Kurumi - Female, MS 3rd year. Rentaro's 7th girlfriend. Glutton. Fierce when hungry, tsundere when full. Fast metabolism. Gluttony role.

Meido Mei - Female, Age 19. Rentaro's 8th girlfriend. Hahari's maid, serves Hahari. Has rainbow eyes but keeps them closed. Calm.

Sutou Iku - Female, Age 15 (1st year HS). Rentaro's 9th girlfriend. Masochist. Baseball club. Boyish. Uses 'boku' for 'I'. Gag character 4.

Utsukushisugi Mimimi - Female, HS Junior. Rentaro's 10th girlfriend. Narcissist, delivers newspapers, maintains herself. Beautiful appearance and heart.

Kakure Meme - Female, Age 15 (1st year HS). Rentaro's 11th girlfriend. Timid + low self-esteem. Hides face with bangs. Can use 'Misdirection' to move quickly by focusing attention on dolls.

Iin Chiyo - Female, Age 12 (MS 1st year). Rentaro's 12th girlfriend. Rentaro's cousin. Grumbles "Ugh" while trying to correct things. Model student.

Yamato Nadeshiko - Female, Age 24. Rentaro's 13th girlfriend. Uses terrible English and grammar. Loves America and freedom. Japanese teacher. Pretends to be American but is Japanese. Gag character 5.

Yasashiki Yamame - Female, Age 15 (1st year HS). Rentaro's 14th girlfriend. Gardening club. Cherishes life and is very considerate. Walks on stilts, 2m tall. Has a butterfly on her head. Says "Yooo....".

Momi Momiji - Female, Age 14 (MS 3rd year). Rentaro's 15th girlfriend. Touch fetish, very skilled at giving massages.

Yakuzen Yaku - Female, Age 89. Rentaro's 16th girlfriend. Kusuri's grandmother. Has an 8-year-old body due to immortality drug. Doesn't know much about modern trends.

Torotoro Kishika - Female, Age 17 (HS Senior). Rentaro's 17th girlfriend. Kendo club captain. Regresses to an infant state when treated like a baby.