Ruth might have given her ideas but Mimi had other plans and it sure was as risky as hell. But then, this was for Arianna; she would do anything to get her back.
Right now, Mimi was dressed in what could be described as a slutty dress. With half of her thighs exposed and her boobs almost popping out of the dress, Mimi attracted attention - which she wanted. However, that attention was reserved for a different set of people. Mimi set her eyes on men from the Red Giant gang.
To hide her identity, she was wearing a short straight bob wig with flat Bangs, her face coated in thick layers of makeup that Mimi swore even her mother wouldn't be able to recognize her if they happened to cross path - although her mother would have a lot of questions to answer if she bumped into her in this club without her father by her side.
All in all, it was a good thing. So if her crazy plan failed, they wouldn't be able to trace her back to her place.