The song is called "Flower World".

According to the query of NetEase Tiyun Music, "Flower World" is a song written, composed and sung by Wang Menglu.

Relevant lyrics are: You happily accept the favor of all living beings in the flowery world, the spring breeze lifts your skirt, I quietly guard the window sill in a corner in the north of the city, watching the bright white moonlight, Moss has grown outside the courtyard, and the umbrella is open due to the light rain.