What would you think if you noticed a guy wearing a thong?

I've often wondered this because I wear thong underwear quite frequently. Even though I take care to wear a belt and tuck in my shirts, I'm still a bit nervous that it will show. I also like how they feel when I workout, but am afraid of changing in the locker room. Im just curious as to what people's reaction would be. Should I be worried?
What would you think if you noticed a guy wearing a thong?
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