The cat was out of the bag now… Mimi had walked in on Alex while he was having sex with her manager. And she had no idea what she was looking at. There was a visible look of confusion on the sheltered young idol's face, as she tried to understand what was going inside of Ji-An's pussy, and why Alex did not have one as well.
After all, she knew nothing about the male anatomy because her parents had never actually taught her basic sexual education. This meant that Mimi was entirely unaware of what she was witnessing. Ji-An, of course, began freaking out when Mimi asked what was going inside her, and whether or not she was in pain.
"Mimi! Don't look! You can't watch this!"