The story focuses on Komugi (中原 小麦) a lovely 17-year-old idol and cosplayer who can transform into a magical girl "Nurse Witch Komugi" in order to save the world from invading alien viruses.
Previously, the OVA was made into two series, including Nurse Witch Komugi-chan Magikarte Z (released in 2002), and Nurse Witch Komugi-chan Magikarte Z (subsequently released in 2004). I strongly recommend this series if you like anime idol girl.
Main Characters
Yoshida Komugi (中原 小麦) voiced by Tomoe Kei (奎依)
Kokona Saionji (西園寺 ここな) voiced by Yamazaki Erii (エリイ)
Kisaragi Tsukasa (如月 ツカサ) voiced by Koichi Makoto (眞琴)
Source: http://www.animate.tv/news/details.php?id=1445325122