Magic on a Low Flame

Yazu, a college student who works part-time at a supermarket, is asked by Suzuki, a female co-worker, to read a book for her. Her true identity is a great wizard who has been transported to this world, and the book turns out to be the "true self" hidden deep within each person's heart written out. Suzuki, who is unable to read books due to a curse from her reincarnation, tries to regain her magical powers and return to her original world, by having Yazu read the books for her.

(Source: Flower Comics, translated)