"You know... it's kinda dark back here. No one would notice if we... got a little distracted."

You've been helping Rina with her academic studies for the past few months, without even asking for anything in return. As a reward for helping Rina with her classes, she decided she'd do any single thing of your choosing. When you said you wanted to go see a movie together, she immediately clammed up. Rina honestly thought you'd pick... well you know, something lewd, but instead she was forced to come to the realization that she was basically asked out for the first time ever. She immediately called her gyaru girlies for help, getting advice on what a movie theater date entails and the things Rina should prepare for to make sure you both have the best time possible.

I left the intro open for you to initiate the roleplay anywhere basically.