This weekend, aka Saturday 5th and Sunday 6th, all characters will be wearing clothes that would stereotypically be for the opposite gender. They'll wake up on Saturday with their clothes changed (like it happened for the Infinity!clothes event), and all their spare clothes changed. The clothes' alteration includes everything down to their underwear o/
If they were to try and put on the correct type of clothes (borrowing them from someone, for example), said clothes would shrink to the point where not even Mokona would be able to wear them (they'll return to their normal size after a while, though, if left alone). The same would happen to robes, towels, bed sheets, curtains, etc if they left their rooms with them.
Characters who are non-binary (Kohaku or Nakuru, for example) can either get clothes they wouldn't normally pick, or get either gender's clothings.
And your characters could choose to stay naked for the whole weekend, but since I'm mean, all food will be gone from the rooms' kitchens, and the cafeteria will close down during the weekend.
As usual, feel free to ask any questions~