Halloween // What should my Halloween costume be?

I (20M) work in Starbucks and on Halloween we will be allowed wear our own costume from home! I can't wait. My crush works with me that day and obviously a shirtless costume isn't allowed but I'm thinking one like a Greek God where I only have to wear half a shirt so she can still see my gym progress. What do you guys think? I want one that's both cool and attractive.