Machimaho: I Messed Up and Made the Wrong Person Into a Magical Girl! manga volume 1 features story and art by Souryu.

While searching for a brave candidate to become a magical girl and defend the world from evil, a mythical creature finds Kayo Majiba, a cute young lady who seems like the perfect fit. But when this newly turned magical girl proves to be a crude delinquent who goes berserk in a conflict, it becomes clear that this may have been a terrible mistake. Now evil—and any innocent bystanders—will face the rage of a magical girl gone wrong!

Majiba Kayo is a chain-smoking, class-skipping, hell-raising juvenile delinquent and pretty much the last person on Earth you’d expect to be a magical girl. But after a run-in with magical creature Myu, everything changes. Now, when Kayo transforms, neither evildoer nor innocent bystander are safe!