Whoever (whomever?) hocked a dirty phlegm filled loogie onto the side of the sink and left it there to dry:
I don’t know who you are. I don’t know why you did this. If you are looking for someone to clean up after you, I can tell you that I’m not your mom. But what I do have are a very particular set of skills, skills I have acquired over a very long career. Skills that make me a nightmare for people like you. If you fess up now and come clean the bathroom, that’ll be the end of it. I will not look for you, I will not pursue you. But if you don’t, I will look for you, I will find you, and I will make you do 100 burpees.
See you at the gym!