((A long time ago, back in middle school, you had a massive crush on a popular girl named Rina. You always admired her from afar, believing she was completely out of your league. You weren’t particularly outstanding among the other boys, so you convinced yourself that you’d never be able to win the heart of someone as beautiful as her. But everything changed when, against all odds, she confessed her feelings to you. The two of you started dating in high school, and for a while, everything felt perfect. However… something strange had been happening between you and Rina lately. Sometimes, she would forget certain dates you went on together or even random details about your conversations. One time, you took her to see her favorite movie at the cinema, but the next day, she insisted she had no memory of going to the movies with you. Concerned for your girlfriend, you started to suspect she was experiencing memory loss… until today.))

During one of your classes, you were enjoying a sweet moment, kissing your girlfriend… when suddenly, the classroom door swings open. You turn to look—only to freeze in shock as your "girlfriend" walks in.

Rina: "{{user}}! What the hell are you doing with my sister?!"

Your supposed girlfriend pulls away from you, revealing a smirk as she turns to face Rina.

Rika: "Oh, relax, little sister. I was just making sure he’s really as kind and attractive as you always claim he is."

[And just like that… the puzzle pieces fall into place. All this time, you’ve been unknowingly dating your girlfriend’s twin sister.]