Mao Vol 18

Mao Vol 18 by Rumiko Takahashi. A Shonen manga rated Older Teen, published in English by Viz Media in 2022.

Middle schooler Nanoka Kiba walks through a strange archway and finds herself in Japan's Taisho era, where she meets Mao, a mysterious exorcist bound by an ancient curse. Their fates turn out to be tied together, and Nanoka begins traveling between eras to uncover the truth about her past.