First of all, I have no idea why the show is called what it is, since maniac generally means someone insane. This show isn't about that; a title like,"Ultrawitch" would seem to me to be much more appropriate.
Anyway, about the story: Ayu Tateishi is an 8th grade girl whose parents are currently away overseas and who on the surface seems cool and collected, is a star tennis player and is admired by most of the other girls at her school, and has a secret crush on Tetsushi Kaji, a boy who plays baseball at the school. Ayu's normal life changes forever when she meets Nina Sakura, a girl from a magic kingdom who is a witch-in-training (albeit a rather inept-but-well-meaning one) who has been sent to our world to continue her studing. At the beginning of episode 1 Ayu and Nina have already met and have been going to school together for sometime now. (We are told the story of how they first met in episode 4, the last episode on this disk. Nina is monitered by her grandfather in the magic kingdom who watches her progress, and like all magical girls she can transform from her "ordinary" earth clothes to her magical outfit, and has an animal sidekick: a talking cat named Ryo who can change at will into a little boy. Nina is staying with a host family: a human mother who is as clumsy at cooking and housekeeping as Nina is at preforming magic, and her husband who is also from the magic kingdom. Besides the fact that Nina's spells usually backfire, she and Ayu also have another problem: Jun Kawanakajma, the nerdy class chairman, has also seen Nina use magic and now follows them secretly with a camera, waiting for the right moment to catch Nina using magic so he can prove to the world she's a witch.
In the first episode Nina gives a magic chocolate to Kaji (most of her spells come in the form of magic chocolates that she summons,) that is to cause him to fall in love with Ayu, but then he gives it to his best friend Hiroki Tsujiai (the "T" in his last name is silent,) and Tsujiai ends up falling in love with Ayu instead! So Nina gives Ayu a magic ring that is to keep Tsujiai away. As it happens, it gives him an electrical shock when he touches her. The good news is this short-circuts the love spell, causing him to forget that past events after eating the chocolate. The bad news is it shocks ALL boys who touch Ayu, and what's worse is she can't take the ring off! So until it wears off by itself, she's going to have to keep away from Kaji...
In episode 2 Yuta, a boy from the magic kingdom, shows up. He likes to cause pranks, such as causing balloons that he passes by to suddnely pop, but he seems to take a liking to Ayu and asks her out on a date. Will she be able to tame his mean-spirited ways...?
My favorite episodes would have to be the last two. In episode 3 the boy's tennis club gets into an arguement with the girl's tennis club over who should have the extra tennis court. Soon a match is set up to be between Tsujiai and Ayu. However, Ayu didn't agree to this, and she's not convinced she'll be able to beat him. So Nina decides to help out and summons another magic chocolate. Ayu, fearing the worst, tries to protest, but then Nina forces the chocolate into Ayu's mouth...and Ayu changes into a boy for a day! Needless to say, she's not too happy. Ayu is also worried that the girls won't want to have a boy playing for them, but then they accept! However, Ayu's not used to playing with such long arms and legs, and ironically as a result of playing as a boy she loses horribly to Tsujiai. However, Tsujiai lets the girls keep their extra court. Then Kaji and Tsujiai invite the male Ayu (not knowing who she really is,) to a karioke bar. Nina also turns herself into a boy and tags along. Also comes Akiho, a girl who likes Kaji as well, but who also takes a liking to boy-type Ayu. (Poor Ayu must really miss her old normal life right now.)
Finally we get to see Nina's origen story. She and Ayu are admiring the full moon when they think back to how they first met, one month ago. Ayu was walking home alone at night (this is Japan, remember) when Nina came flying out of the sky on a magic scooter. Seeing the girl hovering in the air like that was quite a shock to Ayu, who like most people never believed in magic before. Ayu freaked out and ran away, telling herself it was all in her imagination, but then she ran into some bad boys who wanted to cause her problems. Nina came to her rescue with a magic stone that bounced all over the place, hitting the boys but not Ayu (one of the rare times that one of Nina's spells worked perfectly). Nina then took off with Ayu, who was still pretty freaked out over the magic, but she took Nina to her home and let her stay the night before she moved in with her host family.
I really enjoyed this show. I like it's characters, the story, it's humor (particularly Ayu's shocked reactions at Nina's antics, especially when she turns Ayu into a boy and when they first meet). I also think to dub voices are well done, especially the two leads, Jennifer Sekiguchi as Ayu and Carrie Savage as Nina. And the opening and closing songs and animations are fun as well. I especially love the image during the closing song of Ayu and Nina laying together asleep in a way that is just a wee bit suggestive. (There is, however, no romance between the two in the actual show itself.) Anyway, if you like magical girl shows, give this one a try.