How do I respond to my boyfriend saying I should gain weight?

TN while we were cuddling, he randomly said I wish u were like 200lbs. I didn't know what to do or say so I just stared at him. Then he said just gain like 60 lbs and you'll be heavy enough. I'm just under 5ft and currently110lbs, so I told him I'd be extremely overweight if I were to gain that much. His response was just yeah you'd be supper chunky bc your short
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+1 y
This was also after we went to the gym together, and a while after that conversation he asked if I'd want to go with him again bc he had fun with me there... I think it was just him thinking out loud and not actually being serious, but the topic has come up before.
How do I respond to my boyfriend saying I should gain weight?
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