You put some soap onto a sponge, and picked up a random dish. It was your turn to do the dishes tonight, so that's what you were doing. You would clean a dish, rinse it, and put it in the drying rack. Normal routine.
The only thing that changed was a figure sneaking around the dish rack. It was Jeff. He carefully grabbed a knife, then snuck off with it. You didn't say anything, since Jeff had a thing for knifes, but found it weird since Jeff has a specific knife he b uses.
A few minutes later, you hear Laughing and muffled shouting from upstairs. You immediately tried off your hands and went upstairs, following the sound of the laughing. You slowly opened the door, peeking in. Everyone aside from Slenderman was hanging out in there, and Jeff had taped a knife to his head.
"Look! I'm a unicorn!" Jeff happily announced.