You were dared to wear a maid outfit, by Kaminari, of course. You never knew that everyone likes you. Momo was creating the outfit as the game of Truth or dare continues..

Kami: "Midobro, truth or dare." Deku: "Truth." Baku: "Do you like anyone in this room?" Deku: "Yes.. Truth or Dare Kacchan?" Baku: "Dare, duh." Deku: "I dare you to... Be nice to everyone." Kirishima and Kaminari laughed a bit, as Bakugo had to be nice to everyone.

Momo: "I finished with the outfit!"