Eiken(エイケン?) is a heavily fanservice-themed manga and anime series created by Seiji Matsuyama. The story depicts the life of schoolboy Densuke Mifune after he is forced into the mysterious Eiken Club, which is populated only by females, several of whom have ridiculously enormous breasts.
The manga series ran for eighteen volumes, and additionally included a series guidebook. A number of radio drama episodes and a two episode OVA (the latter roughly based on a volume 3 storyline) have been produced.
The first twelve manga volumes have been released in North America. The first three volumes were rated 16+, while subsequent volumes were rated 18+.
The red-headed Chiharu is considered one of the most attractive girls at Zashono Academy. Her breasts initially measure at 88cm (F-cup) and progresses throughout the series to beyond 100 cm. She's shy around boys, because she came from an all-girls school. Densuke tripped on a banana peel and landed hands-first on Chiharu's chest the first time they met. Kirika later finds out that her fondness for Densuke stems from this encounter, as he was the first boy to manage to touch her large bust. Like Densuke, she's a recent member of the mysterious Eiken Club and always finds Densuke falling onto her bosom or stumbling into her bust while she's undressing one way or another (accidentally, or as one of Kirika's own brand of practical jokes), yet she doesn't seem to hold anything against him for it, and also has feelings for him. Because of the large size of her breasts, they are very sensitive, and when they are forcefully touched or squeezed Chiharu appears to be overcome by the sensation. Due to the size of her breasts, she is occasionally forced to wear bras several sizes too small for her, which sometimes leads to her breasts popping out of them. She reveals in later chapters of the manga that she is happiest when Densuke is "near her".
The protagonist. A plain boy no one seems to notice, Densuke was forced into the Eiken Club after an accidental run-in with Chiharu, whom he develops a crush on. He eventually accepts his place in the club, despite being tormented by Kirika and the other mishaps that befall him, i.e. being beaten, violently crushed (Kirika, Yuriko) or electrocuted (Kyoko) by other members. Densuke is frequently forced to cross-dress by Kirika, a hobby of hers.
Not much is known about Kirika, the purple-haired amazon that runs the Eiken Club, and has a 99 cm (G-cup) bust. She likes putting Densuke in awkward situations for her amusement and loves sucking things that look like phallic symbols. In many cases, it's revealed she doesn't wear underwear. Unlike Chiharu, she has a fondness for teasingly "squashing" Densuke's head in her cleavage or stuffing his face between her buttocks, or engulfing his entire head between her breasts. Sometimes she even carries him with his head mashed between her breasts. When Kirika is sick she acts completely opposite than she does when she isn't sick and it has been shown that after she gets better she doesn't remember anything that occurred when she was sick. It also has been hinted that she likes him like in Volume 2 of the manga when she catches a cold and starts acting different she confesses that she has been trying to get close to him and she also tries to kiss him. Also in Volume 5 when she starts acting weird because of her allergies she starts acting like she did when she was sick and she tries to kiss him again which is another hint she might like him. She is also very gluttonous being described as being like a champion eater when she was trespassing and ate inside random peoples' home.
The pink-haired Komoe is the youngest member of the Eiken Club at 11 years old, but also the most well-endowed, with an 111 cm bustline. Komoe is very clumsy, but always striving to do her best. Her clumsy mistakes often leave her exposed, and she has a habit of accidentally hurting and squashing Densuke with her breasts when falling on him.
Grace is a blonde-haired British girl who was born and grew up in China. She comes from a fortune-tellers' family and her father is a successful world-class enterpriser, also she is also very good at acrobatics. She seems to have a bit of feeling for Densuke as in the original manga, her words with Densuke in the speech bubbles are often ended with love-hearts. She has a 77cm (A-cup) bust. She is very strong, and hides her strength by wearing heavy jewelry. Densuke has at times been severely hurt by her heavy jewelry falling on him.
Kyoko is the small blue-haired girl who runs the science division of the Eiken Club, and would seem to be the second-in-command of the club. Despite her age, she looks a lot younger than she really is. She has a 55 cm bust. She often hurts Densuke with her various inventions (rockets, electrocuters).
Chiharu's energetic sister, she looks like a short-haired cheekier version of Chiharu. Despite being fully aware of Densuke and Chiharu's feelings for each other, Yuriko likes trying to get between them, most often attempted by seducing Densuke with her toned runner's butt. She likes rubbing her sister's breasts to tease her because of her own lack of giant breasts, as she only has a 73cm (A-cup) bust. Densuke finds out later in the manga that her "weakness" is her butt, which is often focused on in both media. She often greets Densuke by jumping into him, landing seated on his face and usually leaves her buttocks or crotch in his face.
Sensei is never named, though she is a teacher from Zashono Academy, she often laments the fact she always seems to go unnoticed by her students and peers, not to mention the fact that they never seem to remember her name. She has bright green hair and an 85cm (C-cup) bust. Her running gimmick is that Chiharu always stumbles upon her and Densuke in compromising positions, each time requiring Densuke to spend more time allaying her fears (from a week to a hundred days). She likes spanking herself. In the manga it shows that Teacher has a crush on Densuke because he always cheers her up after something bad happens. She shows she has a crush on him in Volume 4 chapter 26, she starts to tell Densuke that if she was Chiharu's age she would go out with him. In Volume 2, Densuke finds that Teacher looks beautiful without her glasses.
Teddy is a very shy young girl, who wears a giant bear suit most the time. Only Densuke has seen her outside of the suit where he repeatedly falls face-first into her butt. Not much else is known about her except that she has an older sister, who also wears a similar suit.
Chiharu's cousin, who also has a crush on Densuke. Her timetable always seems to be occupied by many part-time jobs. Densuke eventually finds out that she is secretly funding detectives who promised to find her long-lost father who left almost without a word after the divorce (due to the bankruptcy of his factory). She has an 84cm (C-cup) bust.
She is head of Zashono Academy's Committee of Student Accountants. She had mysteriously returned to the academy over a two year span with an immediate action of carrying out her own budget plan: to forcefully cancel all the activities of all the clubs in the academy, despite all the dirty tricks she has in mind. When the Eiken Club was in grave danger (Chiharu had been forced to fill a resigning form, and the club building destroyed), it was Kirika's turn to save the day by stating the TRUE reason where exactly had the money for running the clubs had gone and why would Cho pay so much attention on the crushing of the Eiken Club. In fact, Cho had also been slightly infatuated with Densuke, unnoticed even by herself.
The ex-head of the Supernatural Club in Zashono Academy, a slim and weedy girl whose body is dotted with bandages (They cover the countless bruises and wounds caused by falling due to fainting resulted by her anemia). She and Densuke first met when she bumped into him and got accidentally groped. Under the threat of the abolishment of her club, she is used by Cho as a bait in order to lure Densuke into quitting the Eiken Club, but is soon defeated by his kind heart and gentleness, and she asked for the abolishment of her club herself. She soon becomes a member of the Eiken Club, and after another accident with Densuke, becomes the new leader of Eiken.
The mother of the Shinonome family, and also possessor of the largest bust size, measuring at 123.5cm (K-cup); She says they were similar in size to Chiharu's when she was her age. She once met Densuke randomly on the street and brought him home. Keiko was wearing a very revealing swimsuit at the time, making for an awkward first encounter. Chiharu was surprised to see Densuke at her house, much less with her half-naked mother's breasts wrapped around him. Keiko is the typical ditzy mother type, however she makes some questionable choices; in the final volume, she prevents Densuke from going to Chiharu's rescue by trapping him between her enormous breasts, as she admits to him she has feelings for him herself.
The younger brother of Chiharu. He first appears pretending to be Chiharu in order to test Densuke. He is practically Chiharu's twin, and it is hinted that he is interested in Densuke, whether that is true or not, is not known.
He is the champion of the previous academy tournament who has returned from America to win the heart of Chiharu Shinonome. He is aware of Densuke's feelings for her, and feels that competition is the only way to decide who should get the girl. Kurosawa also berates Densuke for accidentally groping Chiharu, but accidentally reveals that he was peeping on the Eiken Club with a hidden camera. He has blue hair, but in the OVA it is later revealed to be a wig.
Eiken received crushing criticism in the United States. It has been accused of being "obscene" and "lacking substance". Jason Thompson gave the manga a zero-star rating in his review of the series in his Manga: The Complete Guide. The review was:
"Actual pornography disguised as romantic comedy pseudo-pornography. Densuke, a clumsy teenager, enlists in his school's all-girls Eiken club, which has no real purpose (the name is meaningless) other than to surround him with stereotypical women into whose enormous, lemon-shaped breasts and giant butts he constantly stumbles. The main thing distinguishing this from other fanservice manga is the complete lack of plot and the revolting artwork, including a sixth-grader with breasts so large they look like giant testicles, and numerous obscene shots of women eating Popsicles, veiny chunks of beef, and the like. Probably intended as a parody of 'normal' shōnen romantic comedy manga, it is still almost unreadable. Early volumes were labeled as 16+ before switching to the more appropriate older rating."
Stig Hogset gave the anime a one-star review on THEM Anime reviews, calling it "one of the most exploitative, demeaning anime titles I have ever seen". He went on say that "Eiken is like an hour-long nightmare of sexual innuendo of the creepy kind... you'll never find a bigger collection of 'wrong' anywhere else."
The anime and first volume of the manga were given "F" and "D+" grades at mania.com, respectively.