Why would a guy squint his eyes?

On the first week of school when we first met he asked my name and if I had a boyfriend and was like “you’re my prom date okay?” And I agreed but fast forward into a few months of school I noticed when he sees me he always squints his eyes? And last week he sat at my group and when I looked at him he was talking in my group but mainly looking/squinting at me while he was talking but he was smiling while doing it? And it lasted for a long time even when I looked away he was still squinting and smiling? Why’d he do that? Lmao
Why would a guy squint his eyes?
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