Saiko Share definition Flag An asshole who steals your internet friends. Guy 1: "Man, I feel shitty"Guy 2: "Why?"Guy 1: "Saiko happened. "Guy 2: "Damn.." Saiko by Eren Jaguar January 18, 2015 0 0 Get merch Get the Saiko mug. Buy Now — $32.95 See more merch