This one is a hot one. Very young, very thin (almost skeletical), very east-european ethnic (maybe russian, not sure).

She's also known as Brooklyn (My Precious Virgins) and Betty (Glam-Deluxe).

There are 12 sets total, which I know of:

Glam Deluxe - Petite Fascination
Glam Deluxe - Turn Around
Glam Deluxe - What a Mess
My Precious Virgins - Set 1
My Precious Virgins - Set 2
My Precious Virgins - Set 3
My Precious Virgins - Set 4
Nubiles - Set 1
Nubiles - Set 2
Nubiles - Set 3
Nubiles - Set 4
Nubiles - Set 5

I'm starting off with Nubiles - Set 5 because it is my favourite one.