I Cosplayed as a Master, Then Ended Up in the Wrong World

Blurb One:

With a Command Seal drawn on the back of my left hand and a gold ring I'd bought as a substitute on my right middle finger, I headed out in casual clothes, looking very "low-key," and went to a convention not far from home.

I never expected that before I even got to the convention, my vision would blur and I would transmigrate.

Blurb Two:

A mysterious person has recently appeared in the hidden world. No one knows their gender, age, or true appearance. Every time they show up, they sabotage an illegal trade site. The criminals turn up bound hand and foot outside the police station the next day, the money from the illegal deal vanishes, and the goods being traded mysteriously arrive at the police station by courier.

Since no one can find out anything about this person, the entire hidden world is suddenly on edge, and an eerie calm settles over it...

Content warnings:

OOC warning! OOC warning! OOC warning!

The important thing is said three times: everyone is OOC.

The heroine is the strongest, and she loves watching the fun.

Written with the skill of someone who hasn't graduated kindergarten. Read with caution, thank you.

Theme: Love is the greatest power.