I think this is most likely to be a fusion of Cirno, Daiyousei and Lily White

The hat/crown/tiara is Sunny's, the twin tails are debatably also her's (she has smaller ones and smaller ribbons though). Then there's Luna's Moon and Star's...star. Looks like only Clownpiece is left out of the fusion, although she also has long blonde hair and red eyes .

[KN] said:

The hat/crown/tiara is Sunny's, the twin tails are debatably also her's (she has smaller ones and smaller ribbons though). Then there's Luna's Moon and Star's...star. Looks like only Clownpiece is left out of the fusion, although she also has long blonde hair and red eyes .

It can't be Clownpiece since the character didn't exist when this picture was drawn. It's old stuff from him/her^^.
Btw. the character_request was put because I know it was a fusion but I don't know all Touhou fairies^^.

If the picture is before Clownpiece, then the hair seems to be a combination of Daiyousei and Sunny_Milk's tails, Star_Sapphire's hair length, and Luna_Child's blonde hair colour.