Tetsuro Tanaka finds out he's been accepted to a new school. A girls' school, and he's the lone male there. Within a day of his arrival, he's treated to the Alpha Bitch Student Council President and her Girl Posse, and gets himself a Magical Girlfriend, Yayoi Asuka, who shares the name of his childhood friend. He finds himself staying in Yayoi's dorm along with her five friends. Something's not quite right about them. They're all cyborgs, and together they form the Koi Koi 7. Which only has six members. Tetsuro learns about each of the girls he lives with, and they in turn defend him (and Yayoi) from Miya's almost daily attacks.
What starts off like a typical Unwanted Harem turns into a story of conspiracies, things given up and things that want to be regained - a foreshadowed yet powerful Genre Shift. The manga, by Morishige (creator of Hanaukyō Maid Team) ran for 9 volumes, and was adapted into a considerably different anime that nonetheless retains the quirkiness of its source.
This anime provides examples of:
- Ascended Fangirl: Akio the Sentai fan gets a chance to actually be a hero with her powers.
- Attractive Bent-Gender: Tetsuro's female crossdressing identity of Tetsuko is Miya's love interest. Awkward.
- Beach Episode: The final episode, featuring an extended nude fighting sequence. The manga prefers a hot spring for its finale.
- Excited Title! Two-Part Episode Name!: E.g: "Girls Bravo! Sway, Flow! The Counterattacking Miya-sama"
- Gainax Ending: While a DVD omake somewhat helps to clarify what happened, it's still one of the more "huh?" endings out there. The manga ending is somewhat less vague, but equally confusing.
- The Gunslinger: Sakuya, who has a preference for BFGs and Hand Cannons.
- Harem Nanny: Orie. In this case, that means repairing the girls. She's also their teacher.
- Hollywood Tone-Deaf: Miya's rendition of the show's OP. There are no survivors.
- Humongous Mecha: Piloted by Miya and crew. All of them are trashed. Evidence of Shout-Out here as well — most of the mecha are obviously patterned after Zeon Mobile Suits (and one in Episode 5 is the SDF-1 from Macross complete with a ship for an arm)...
- Innocent Cohabitation: Tetsuro's room is next to Yayoi's. She smashed the wall to make it a two-person room.
- In the Name of the Moon: Done when the girls first appear as a team, with the expected heroic music and posing.
- Love Is in the Air: The events of episode 12 lead to Tetsuro being swarmed by a herd of girls in love with him. Yayoi and friends are spared from this by being cyborgs.
- One Steve Limit: Two Yayoi Asukas. It's best that Miyabi and Miya don't get confused either.
- Prehensile Hair: Miyabi, who also has some shapeshifting powers.
- The Psycho Rangers: Miya creates a squadron of her closest followers.
- Squashed Flat: Four of the girls are trampled flat.
- Verbal Tic: Yayoi's "desu" is the most obvious (it even makes it into the episode titles), but most characters have one.
- Winged Humanoid: Both Yayois. White wings and black wings, respectively.