I work at Starbucks, I have a crush on a customer, what to do?

I am a Starbucks barista, and I get a frequent customer who I really want to ask out, his name is Kale. I could get fired if he were to get offended and tell my boss, if I were to ask him out, but if he doesn't than I get a date, and my job... I don't know what to do? Cause really we really are supposed to keep a very professional attitude at work... But we get along, and I know he's gay cause my friend is dating his ex... Yes I live in a small town.