Ultra Maniac (ウルトラマニアック, Urutora Maniakku?) is a manga series written by Wataru Yoshizumi. The romantic comedy series features seventh-grader Ayu Tateishi, a tennis club member, and her transfer student friend, Nina Sakura, who is actually a trainee witch from the magical kingdom. It premiered in Shueisha's Ribon manga magazine in February 2002 and ran until January 2004. It was also published in five collected volumes by Shueisha. Viz Media licensed and released an English translation of the series in North America.

The series was adapted into a 20-minute anime OVA, released August 6, 2002. Later, it was also adapted into a 26-episode anime television series. Both were produced by Ashi Productions and Animax. The anime series premiered on May 20, 2003 in Japan on Animax, and was later licensed for Region 1 distribution by Geneon Entertainment

Source: Wikipedia