Isabella Theism

Isabella Theism (イザベラ＝テイズム) is a necromancer and member of Necessarius, introduced in Toaru Majutsu no Index SS: Agnese's Magic Side Work Experience.

Appearance
Isabella is a gaunt, silver-haired and brown-skinned woman, who dresses in tattered rags, clothing of the dead.

Toaru Majutsu no Index SS: Agnese's Magic Side Work Experience
During Agnese Sanctis, Lucia and Angelene's training for Necessarius, Isabella fought Stiyl in a mock battle in Barcelona, Spain, which the nuns were to forensically clean afterwards. In the simulated battle, Isabella was playing the role of a member of the magic cabal Armada who had been burying people alive to create a graveyard for the burial shrouds needed for her magic.

Later on, she and Stiyl watched as the nuns dealt with a curse-fearing priest, who had applied magical cleaning techniques in order to frame and dispose of a Haitian restaurant owner whose wife had apparently died from a curse, with Agnese dumping the remains of Isabella's fake corpse on the priest. With the girls having passed the test, Isabella noted that they were about to be very busy.