I think touch can be very, very therapeutic. My therapist hugs me every session, sometimes more than once... She holds me/us if we're crying, sits by us, holds our hand, etc. I even call her to come in after hours for extra hugs when it's been an extremely rough day. It is something, however, that is supposed to be initiated by the client. So I think you have to point-blank ask him "is it ok to ask for a hug" and brace yourself for the response to go either way.