Mistress Gaia wanted to show her friend that peeing on losers was a good way to deal with them and to make them learn their lesson in a cruel manner. The mistress brought out a loser and she had her friend try what she saw her do. The two of them had a great time peeing on him and watching him drink the urine. They also recorded it to watch later.
When it comes to torturing people for her own fun, this mistress is heads and shoulders above the rest. She knows what to do and how to do it to achieve whatever she wants. That is why she went out of her way today to make this guy drink her urine. He had no choice but to do it and when he was done, he knew he would never want to mess with her again.