I did an outcall with one of the girls from Alpha last year. She kinda peed on me when we were showering, but it was an accident, I think. She told me she was just marking her territory. ;-)
Ellie at alpha mentioned that she's open to it when I contacted her, but I haven't booked with her yet. Also giving is not my thing. She's very responsive on twitter if you ask politely. I got a feeling that she's really into it.
Good luck!