Itsudatte My Santa! is an anime OVA series based on the manga by Ken Akamatsu.

The main character of Itsudatte My Santa! is a lonely boy who hates Christmas. It turns out he was born on Christmas Eve, and his parents named him Santa. As a child, he never had any festivities, such as birthday parties.

The story opens on Christmas Eve, where Santa is suddenly approached by a girl named Mai, who claims that she is Santa Claus. It turns out she is a student at the Santa Claus Academy, and she has problems using her magic. She can only conjure up things that start with "san" in the Japanese language. Mai was sent to Santa with a mission to cheer him up; however, she ends up falling in love with him.

When Mai first comes to Santa, she appears in the form of a junior high student. However, when Santa starts to believe in Santa Claus, Mai has enough Christmas powers to change into her adult form. In the anime, this is done in the "typical magical girl" style. In the scene where Mai transforms, she becomes completely nude, and has sudden growth spurts in certain regions.

While the manga only tells the story of how Santa meets Mai, the OVA adds a second episode with a story that's not told in the manga. The OVAs also introduce characters that aren’t in the manga: Sharry (Mai's best friend and rival), MaiMai (Mai's younger sister), and Noel-sensei (a teacher from the Santa Claus Academy).

Itsudatte My Santa! is an over-the-top anime with a Christmas theme. However, it's not an anime that's being aimed at a young audience. When FUNImation released Itsudatte My Santa!, they rated the series with a TV-MA. I agree with this rating, since it has some nudity and fanservice; the fanservice is made up primarily of panty shots of Mai. Personally, I think Itsudatte My Santa! is appropriate for anime viewers who are 18 years of age and older, especially since it has a TV-MA rating.

Title	Episodes	Release Year(s)	Director	Studio	N.A. Licensor
Ittsudatte My Santa!	2	2005	Noriyoshi Nakamura	TNK	FUNimation Entertainment