Mysterious Magical Girl Marii-chan (ふしぎ魔女っ子マリーちゃん), Mary, the Mysterious Magician in the LUK Internacional dub, is a Magical Girl series in Crayon Shin-chan which is a parody of the Magical Girl genre. The first time it aired was in episode 335 and the last one being in episode 348, after this Marii was only shown in cameos, the last one being in episode 540 as a figure in Kazama's room along with other figures, including one of Moe-P.
The series' main song is I'll cast a spell (魔法をかけてあげる).
Toru Kazama is an obsessed fan of Mari-chan, but will not admit it because of shame as the series is aimed at a female audience.
Marii was sent to the human world because she failed an exam and according to her teacher it was the only way for her to not fail her year of high school. When she is sent to high school in the human world, nobody has to know she's a magical girl, if someone finds out then everybody who knew her gets their memories about her erased and then she has to start all over again like a new high school student.
Marii Shiwasu (師走 マリー)
The main character of the series, she is a 16 years old brown haired girl with the ability to transform into a Magical Girl, she mostly fights squid or octopus based enemies. Every episode her friends find out she's a Magical Girl and she has to start all over again.
Shiira Kannazuki (神無月 シーラ)
The main villain and also Marii's rival, she wears glasses and is reddish-brown haired. She's also a Magical Girl and sends enemies to fight Marii. She wears a sexy dress that Shinnosuke and Hiroshi like.
Marii's brother, he was cursed by a spell of Shila and transformed into a sea otter.
A brown-haired boy which seems to have interest in Marii, he doesn't mind if Marii is a Magical Girl or not and thinks she should be treated as a normal girl like everybody else. He is also a handsome classmate of Marii attracting girls. He is one of those who discover her true identity as Mari-chan, but later his memory is erased.
Teacher Yamaoka (山岡先生)
Teacher in charge of Marii's class.