The Witch of Sasebo?

Young Karibuchi Hikari is the little sister of Karibuchi Takami, a famous witch who fought against the Neuroi in Europe. Hikari is a hard worker with a lot of stamina, but she lacks her famous sister's magical abilities. When she gets the chance to go to Europe and fight alongside her sister, she gladly volunteers, but first, she'll have to prove herself by competing with another student at her school.