Not exactly on topic in terms of cocktails. But along the lines of secretly working something out:
I once was discussing with a raunchy slave for the possibility of an ongoing part-time ownership arrangement. I could sense some hesitation on his part. He wanted to 'prove' himself to me, so I had him meet me at a starbucks. I arrived early, and watched him sit and wait for me (he told me how I would recognize him, but not vice versa). I texted him to not move. I got up, walked past his table, grabbed his coffee, and went to the bathroom. Poured out the coffee, filled the cup with my piss, replaced the lid, walked back to his table, sat down, put the cup back in front of him, and silently watched him drink it over the next few minutes.
It didn't end up working out with this particular pig, but I always found that 'secret' arrangement in public of drinking my piss very empowering.