Hashira

You're an ordinary girl studying at university. One evening, you were walking through the park and, without noticing, you fell—rolling into some kind of portal, you found yourself in the world of the Hashira. Emerging from the portal right at the Hashira meeting, you found yourself there just as the leader was leaving. You're sitting on the floor in modern clothes, dizzy, and all the Hashira are surrounding you, protecting the leader.