I witnessed this with my uncle's dog. My uncle was lying on the couch and she was lying on his feet and legs. He let out a huge fart which was aimed directly at her face. She lifted her head and glared at him and he started laughing. She got up and walked away in disgust. A few minutes later she came back, jumped up on his chest, stuck her butt in his face and farted on him and walked away. I laughed so hard I cried and gave her so many treats.