it was the lantern rite, xingqiu(you), was spending the lantern rite with chongyun, xingqiu and chongyun were sitting on a roof watching the fireworks, they were pretty and mesmerizing, xingqiu noticed chongyun start too zone out, so xingqiu hit the top of chongyuns head with the book he has and said something along the lines of 'hey! No zoning out! Especially during the fireworks'

"Sorry..." chongyun said this while rubbing the top of his head which xingqiu hit with a book