I'm a huge fan of Rhyll Biest's work and Risk was everything I'd hoped for.
It probably helps that I don't mind a bit of menage as well;) Jane and Michael are awesome characters and while this is a short book and also includes another two special players, Vlad and Lena, Ms Biest managed to get enough character development happening to really invest me in their story. And then the sex happens. And it's damn good.
My only complaint was that I got so caught up in the story that I wanted more of everything, but that's just because I'm not usually a short story kind of gal.
I've reread Risk a bunch of times and every time I'm struck by how well it's put together and how good the writing is. Can't wait for the next book!