sleeveless shirt

Trying to do a model on relationship. We are going to lunch and my partner says. “Please wear something with sleeves.” I do not like wearing sleeves because I get very hot and we will be outside at high noon.

My thought is: You shouldn’t tell me what to wear. I have said before that I get way too hot and feel faint if in a shirt that has sleeves and in the sun. My partner doesn’t like the looks of my arms and thinks it is embarrassing. It is not embarrassing to me but their manual thinks it is and that I should wear something with sleeves. I know this sounds very shallow and petty (which it is!) and it shouldn’t be a problem, but I know it will be with them. They have a right to their opinion as well as I have a good reason. How do I put this in a model? Thanks.