Save Me! Lollipop(2006)

Original title: まもって! ロリポップ

Nina, thinking it was a lolly, swallows an object called "Crystal Pearl". But the candy turns out to be a test for the magicians. To retrieve the crystal, a special medicine has to be made so now Zero and Ichii, the magicians, have to protect her from others while waiting for the medicine to be completed.