Ideal Situation:
Okay, since we're talking ideal, that would be fantasy. My "ideal" would be very straightforward, with a m/f couple. We would meet at the place of your specification. You two would look at me and say that I would do. I would be taken to a private place of your choice and ordered to strip. The woman would lie back on the edge of a bed , pulling her skirt up and say "Eat." I would begin to worship her crotch with my mouth. She would raise up and push me down further if she wanted me to french-kiss her anus, or pull me higher for her pussy. After a few minutes of this, my head would be pulled away and a cock thrust at me. I would begin to suck until he was dripping in my mouth. Then I would be guided back to the pussy. He would begin to massage and lubricate my asshole until he felt I was ready, then he would slide his dick into me and fuck until he had cum. After he shot his load into my body, I would turn around to clean off his dick with my mouth. Then I would return to her to keep eating her until she was satisfied. If I got him hard in the process of cleaning him, he would fuck me again. This would continue until both members of the couple were satisfied.