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Junta Momonari is a high school student with an unusual problem. Whenever he becomes sexually aroused by a woman, his "female allergy" kicks in, causing the poor boy to throw up. Needless to say, he is a complete failure with women, with no hope in sight. Then, one fateful day, Junta is confronted by an attractive girl in strange clothing who claims to be from the future.

The girl gives Junta her name as Karin Aoi, and tells him about how the world has become terribly overpopulated in her time, to the point where having more than one child is a crime punishable by death. At the root of the problem is a family of "Mega-Playboys": people with sexual charisma and impulses that lead each of them to have 100 children that carry the Mega-Playboy DNA, causing them and all their descendants to each have 100 children as well. All this started with a single Mega-Playboy, whom Karin has travelled back into the past to deal with.

Karin reveals to Junta that she is a "DNA Operator". Her job is to make alterations in people's DNA that will change their nature for the greater good of society. She intends to shoot the original Mega-Playboy with a DCM ("DNA Control Medicine") bullet that will alter his DNA in order to relieve him of his mega-playboy qualities, thus preventing the overpopulation problem from ever happening. She can then return to the future to receive the reward that will allow her to finally get the "nice husband, cute pet, and sweet, sweet home" she yearns for. She confirms Junta's identity, then, to his shock, promptly shoots him.

It seems that Junta, the boy who couldn't look at a naked woman without throwing up, was destined to become the original Mega-Playboy later in his life. Escaping back to her time machine, Karin arrives to a message from her boss in the future. Her hopes for a commendation on a job well done are dashed when her rather upset employer points out that the DCM bullet she was supposed to use on the Mega-Playboy was left behind in the future. By shooting Junta with the wrong DCM bullet - one which Karin planned on using to create an ideal husband - rather than eliminating the Mega-Playboy, Karin actually created him!

Now unable to return to the future until she sets things right, Karin decides to improvise by making Junta get together with the only girl who does not give him an allergic reaction: his childhood friend Ami Kurimoto. But there is a slight problem: not even Karin herself is immune to the Mega-Playboy's charms!


Junta Momonari (桃生 純太, Momonari Junta?)
Voiced by: Keiichi Nanba (Japanese), Liam O'Brien (English)
A high school boy with a peculiar allergy to girls: he vomits when sexually aroused. He gains the ability to transform into the Mega-Playboy practically at will, after being shot by Karin's first DCM bullet. Junta also gain psychic powers along with his Mega-Playboy charm, this includes the ability to teleport and telekinesis.

Karin Aoi (葵 かりん, Aoi Karin?)
Voiced by: Miina Tominaga (Japanese), Jessica Calvello (English)
A sixteen-year old DNA Operator from the overcrowded future, sent back in time in order to prevent the advent of the Mega-Playboy using DCM. All she wants out of life is a nice husband, a cute pet, and a sweet home.

Ami Kurimoto (栗本 亜美, Kurimoto Ami?)
Voiced by: Hiroko Kasahara (Japanese), Rachael Lillis (English)
Junta's childhood friend and schoolmate, and except for two instances, the only girl who doesn't bring about an allergic reaction in him. Also the only girl immune to the Mega-Playboy's ability to seduce women, something Karin considers a key part in the plan to stop the Mega-Playboy: if Junta and Ami stay together, she can nullify the Mega-Playboy's charms and the future won't be overcrowded.

Tomoko Saeki (佐伯 倫子, Saeki Tomoko?)
Voiced by: Megumi Hayashibara (Japanese), Veronica Lake (English)
One of the most popular and beautiful girls in Junta's school, and the ex-girlfriend of Ryuji. She falls in love with Junta because of his Mega-Playboy powers; in fact, these powers manifest for the first time in front of her. Apart of this, she's a quite lonely girl; her mother died and her father works abroad.

Ryuji Sugashita (菅下 竜二, Sugashita Ryūji?)
Voiced by: Takehito Koyasu (Japanese), Dan Green (English)
Tomoko's wealthy and possessive ex-boyfriend. Actually, Tomoko was trying to gain him back at the beginning of the series, going out on a date with Junta to make him jealous. Later gains powers that rival those of the Mega-Playboy after being accidentally shot by a second DCM bullet.

Kotomi Takanashi (高梨 ことみ, Takanashi Kotomi?)
Voiced by: Hekiru Shiina (Japanese), Lotus (English)
A friend and classmate of Ami's who has an embarrassing problem similar to Junta's allergy: she farts whenever she gets nervous. She and Junta spend some time together trying to help cure each other of their problems. She's very talented in gymnastics.

Yokomori (横森?)
Voiced by: Ryunosuke Ohbayashi (Japanese), Tristan Goddard (English)
Karin's boss from the future.

Oharu (おはる?)
Voiced by: Eiko Yamada (Japanese), Barry Banner (English)
The AI of Karin's time traveling ship.

Lulara Kawasaki (川崎 るらら, Kawasaki Rurara?)
Voiced by: Sakiko Tamagawa (Japanese), Rebecca Miriam (English)
The Mega-Playboy's youngest daughter and Junta's 101st child (counting 純). In the anime, she is Junta's great-granddaughter.

Mori (森?)
Voiced by: Jun Hazumi (Japanese), Michael Alston Baley (English)
A government official from the future who wishes to use the Mega-Playboy and his descendants for his own purposes.

Kakimaro Someya (染屋 垣麿, Someya Kakimaro?)
Voiced by: Mitsuo Iwata (Japanese), Tom Wayland (English)
A friend of Junta who often pokes fun at Junta's bad luck with girls.

Ichigo Ichikawa (市川 一期, Ichikawa Ichigo?)
Voiced by: Hidehiro Kikuchi (Japanese), Jake Eisbart (English)
Another one of Junta's friends.

Chiyo Momonari (桃生 チヨ, Momonari Chiyo?)
Voiced by: Hiroko Maruyama (Japanese), Lynna Dunham (English)
Junta's mother, she has raised him alone after being widowed. A kind woman, if somewhat of a meddler and tattletale sometimes.

MANGA ONLY

Mako Iwasaki Competitor with Kotomi in gymnastics, tried to remove her competition with the help of her brother, a psychic interested by Junta's psychic soldier abilities.

Source: Wikipedia