Criminal Border by Purple Software

Rin Akinashi (Voice: Cyclamen Kaori)
The protagonist’s long-time acquaintance and fellow classmate.
A paragon of perfection with good looks, exemplary behavior, and excellent grades, she’s popular with boys and girls alike at school.
However, this is merely a mask, hiding the cunning, scheming vixen she really is.
Despite having been raised in a wealthy environment, she has an extreme attachment to money, and earns a fortune working with Hina to operate a large scale business of her own.
When trouble arises in her business venture with Itsuki, she at first attempts to wash her hands of it, but thanks to Hina's intervention she remains to search for solutions with the rest of the gang.
She is meticulous in hiding her own footsteps, and never makes contact with anyone other than Itsuki and Hina.