Gross out on sight

Not many people have this ability. But some do. I am lucky to know one man who can do this, gross me out just on sight. As soon as he walks in, or really if I see him in my peripheral vision, I have this overwhelming feeling to vomit. It just comes up. It gets even better when he gets really close to the counter.
I don't think he ever actually buys a coffee but he grosses me out so much that I don't want him to cause any trouble. He carries around a big 23 oz. McDonald's cup. It's either filled with soda or coffee, but something black, and also not hot. I bet it's at least a month old. And really nobody should drink that. Maybe that's the cause of his looks?...
I always add 3 drops of coffee to the top. Then he sits down. Then he gets back up. Pants fall because he puts his books and maps (though he isn't a tourist) into his waistline. He picks up pants. I add another 3 drops to his coffee. He holds up pants with one hand and spills "coffee" on his shirt. All his money and cards and pens get wet in his shirt pocket. Instead of asking for a towel, he wants me to replace the 3 drops of coffee. His hand touches mine. I vomit in my mouth a little. Bleach my hand. Pray for him to leave. He unfortunately orders ice cream. Touches my hand again. Have to hold in vomit. Swallow vomit. Drink another cup of coffee to get vomit taste out of mouth. Then I pretend to look really busy. He asks for 3 more drops. I can't take it anymore. I tell him it's the last time. He sits for 2 hours. Tries to get more drips. I say he used them all up for the day. There are no more drips for the day. Then he asks me if it's cold outside. I respond "look out the window" since that's all that I am doing right now too.
I hope I don't die.