Getty Images via Brew PR Lenas, on right, with Martha Stewart at Sean Parker's startup launch last summer.
After a two-year engagement, 
Last year they had a child together, Winter Victoria Parker.
The theme for the wedding is Medieval, according to the New York Post.
Who is Parker's bride-to-be?
She's an aspiring musician who's had some success already, having made at least one appearance on MTV. She is a singer/song-writer who can also dance. And she's big in New York society.
We know Lenas because she also played a big role in saving Parker's life when he accidentally ate some nuts a few years back (he's allergic).
New York society blog Guest of a Guest has lots of pictures of Lenas and they kindly shared some of them with us.