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When a person's Instagram photo is so attractive, it gives you a semi-erection, one that's enough for you to question your existence and wonder why you'll never get with someone like that.
Dude: "Hey, man did you see (insert attractive person's name here)'s picture on Instagram? "

Other dude: "Ugh. Yes, dude. It gave me Instacock."
by plowmaster October 07, 2016
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