When you screw yourself over in a video game. The term was coined by YouTuber Charriii5 in his video "Mario Kart 64: The Redemption (w/ Nathaniel Bandy)"
(Playing Mario Kart)
Gamer #1: (throws green shell)
Green Shell: (bounces off wall back at Gamer #1)
Gamer #1: DAMN IT!
Gamer #2: What?
Gamer #1: I just insta-cucked myself
The stare of someone who gets bitched by there significant other
Jake glassberg in Val’s profile pick has a masterful cuck stare