I waitressed in high school. A guy came in to eat with his family (a little girl and his pregnant wife). The wife went to the bathroom and the guy asked for the check, and on the check, he wrote his phone number in the tip area, along with “call me baby.”
I ran his card, waited until his wife came back, and brought over the guy’s card and his receipt. I handed the receipt to the pregnant woman and told her something was wrong with the tip.