Tomonori Iwaki is in his third year of middle school, and is depressed that his homeroom teacher Natsumi Ibata, who he's had a crush on, is getting married. He comes home from school, only to be greeted by a little girl calling him "Darling" and suddenly declaring herself to be his wife... and her three secret agent "dads", who have been assigned to protect her. As much as he dislikes Rizel (who has rubbed him off the wrong way after coming to him while depressed), he realizes he has to be really careful not to make this girl angry or sad — her tears contain nitroglycerin and can blow the Iwaki household to smithereens!
Throw in a Love Dodecahedron and a generous helping of comedic mischief (and a fair amount of drama, of course) and we get this crazy Magical Girlfriend manga written and illustrated by Yukiru Sugisaki, the same woman behind D.N.Angel, published between 2001-2002 under Monthly Ace Next, with a 2-cour anime adaptation in 2001 courtesy of MADHOUSE and IMAGIN.
Rizelmine is the girlfriend to the following tropes.
- Accidental Misnaming: Rizel never gets Ryuunosuke's name right.
- Adaptation Expansion: The manga was only seven chapters long. The anime reaches 24 episodes.
- All Love Is Unrequited: For most of the anime, other than Natsumi's offscreen fiance, this trope holds brutally — Iwaki has a crush on Natsumi, Rizel has a crush on Iwaki, Ryuunosuke has a crush on Rizel (or at least on her bear print panties), Aoi has a crush on Ryuunosuke, Kyouko also has a crush on Iwaki... and they all end up happily paired off, one of them with a dog.
- Brooding Boy, Gentle Girl: Rizel is as harmless as a puppy while her "husband" is pretty angry and depressed about his teacher's engagement.
- Calling Your Attacks: Aoi does this in similar way to Captain Falcon. So do the four foreign Rizel wannabes.
- Cold Turkeys Are Everywhere: The Papas and Mamas insist that Tomonori and Rizel that they must take their relationship to the next level in order to cure her condition (in their own words, do the adult "C"). Cue Tomonori panicking with the letter "C" being mentioned by everything around his house. Rizel thinks it is just sleeping together with no clothes on and counting the stars, which makes him feel extremely relieved. Then the Mamas barge in and say that the "C" stands for "chuu" (kiss).
- Forgotten First Meeting: Tomonori saved Rizel from being hit by a car when he was young.
- Gratuitous Foreign Language: The foreign altered humans Lux (English), Rachel (Russian), Lobelia (Italian) and Lan-Lan (Mandarin Chinese).
- Happily Married: Despite his quirks, Iwaki's mother loves her husband dearly. She barely got upset after finding out that her husband stashed some pornographic pictures in their son's bookshelf.
- Innocent Blue Eyes: Rizel. Seeing how childlike and naive she is, this fits her well.
- Jerk with a Heart of Gold: Tomonori is a jerk to Rizel at first, and even makes her cry. After his Character Development, and after learning the identity of the woman he saved long ago, he becomes better.
- Level-Up at Intimacy 5: The handlers of several countries' supergirls try to get Iwaki to make out with their charges, erroneously because of this trope.
- Likes Older Women: Tomonori, which makes his being paired up with Rizel that much more aggravating for him. Which makes the source of his fetish all the more ironic.
- No Name Given: The "papas" and "mamas" are not given names other than A, B, C.
- Non-Fatal Explosions: Explosions can destroy walls and objects, but can only do no more than giving people a few singes, and that includes ordinary people with no superpowers.
- Nosebleed: Tomonori's father seemingly has a paedophilia fetish and gets nosebleeds once in a while from Rizel.
- Older Than They Look: Rizel, whose growth was stunted when she turned twelve as a complication from the technology involved with her creation. Whenever she manages to overcome those limitations to look exactly her age, she's quite a gorgeous young woman. Ironically, Tomonori's attraction to older women stems from his rescue of Rizel when he was a grade school kid, while she was in her 12-year-old look (and actually looked her age back then), which made her technically looked older than him.
- Once per Episode: In the anime, Rizel cries at least once by the end of the episode.
- Pair the Spares: This is how a number of the issues of the Love Dodecahedron are resolved. Ironically, this includes a dog.
- Parental Substitutes: The three government agents insist that they are like Rizel's fathers or, more precise, "papa desu".
- Porn Stash: Subverted. Rizel dressed up in Naked Apron which she said comes from pictures which apparently came from Tomonori's bookshelf. In reality it was his father who put them in.
- Screw the Rules, I Make Them!: Rizel is so important to the government they bribe Tomonori's parents with free air-conditioning, state-paid home loans and promotions at their jobs to let Rizel stay. Then they make her marriage license (which was filled out without her "husband's" permission) stick, and fly her to Mt. Everest so she can get an apology gift.
- Shout-Out: Sometimes the characters mentions other anime and fictions, such as Doraemon and Steel Angel Kurumi. Lux also drove the KITT in Knight Rider.
- Verbal Tic: Lan-Lan with her "de aru" and Rachel with her "-ski".