The word saibot derives from the very popular character from Mortal Kombat Noob Saibot. With today's internet slang such as "noob/n00b" it is much faster and classier/discreet to call someone a saibot. Only true Mortal Kombat fans will catch on but will not at first realize they're being called a noob.
"Dude, Bryce is such a saibot."
Friend 1: "Did you bang her dude?"
Friend 2: "No, it sucked!"
Friend 1: "Saibot."