When someone receives sexual pleasure primarily from someone else's social media pictures - especially Instagram - with or without having any other kind of relationship with that person, especially when the person who the social media account belongs to is openly in a sexual relationship with someone else. Essentially, when someone cuckolds themselves via another person's Instagram.
"As a popular dominatrix, I have dozens of men every day admit to being my instacucks!"
by NovaleeSnow August 30, 2019
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