Why would the shirt be stuck?

Just to humor me if you would... can you think of a strange and imaginative reason why a shirt that is worn tucked in would be stuck and could not come out of the jeans? I'm thinking of writing a humorous story about a woman whose shirt won't come out and I'd like some strange influences. If you had a detailed answer, you could email it to me too but answering here is fine. I'll give you some of my poetry in response if you'd like.