If you don't like him, then you can just reject him, if not you can just be normal friends with him to see how things goes.
Na, it is just depends on individual view with life. Regardless of one profession, as long you never go cheat, rob or steal money from anyone. Just making a lawful honest living, nobody should/be looking down on you, same goes to prostitution.
As long the spa you are working in doesn't provide "extra service", I don't see any issue with it.
http://buddhism.about.com/od/theeigh...livelihood.htm