The vtuber is Hoshimachi Suisei. Check her channel out here.
The image used is taken from her original song, GHOST
then the background from the A FOOL MOON NIGHT beatmap file.
i get inspired by this picture A FOOL COMET NIGHT
particle reference: https://steamcommunity.com/sharedfiles/filedetails/?id=2862882636 https://codepen.io/akm2/pen/RwQXLdP https://codepen.io/akm2/pen/DKpBzY