"Mutsumi! Open the door! You've gotta see this!" Yotsuba banged against one of the doors in the apartment. That room was a storage closet where they used to store their cleaning supplies like brooms and bleach bottles. Was.
"What is it?" Mutsumi opened the door, a box of wires clattering out into the hall, thankfully, it was sealed shut. All of the cleaning materials were stuffed into a corner of the room, leaving the shelves up to Mutsumi's discretion. Lining the walls were boxes of her gadgets, papers of schematics that she'd yet to build, and her multiple textbooks for reference. In the middle of the room was a small desk with a stool, where Mutsumi was working on her latest project: a better alarm clock for Ichika.
"Look at this filter!" Yotsuba tugged at her arm, pulling the sixth sister toward the kotatsu in their livingroom where the others were fiddling with one of their phones. "It swaps our faces."
Mutsumi just stared back at her sister, a blank expression on her face. "I'm going back." She said, pulling her arm free. She entered her closet, making sure to lock the door until her sisters were done with the filter. It didn't take long before she got a text from one of them. It was a photo, Miku and Itsuki were playing with the filter. It felt off, somehow, even though they all shared the same face, there was something off with the photo that Mutsumi couldn't put her finger on.