noun. Like bejesus and besatan, but more scientology-y.
Real citation: "seven!? how the bexenu did that happen?"
(May 26, 2008, Paradox Interactive Forums, http://forum.paradoxplaza.com/forum/showthread.php?t=354545&page=10)
Made-up citation: "When Thor was a kid, Zeus and Papa Smurf used to scare the bexenu out of him... That's before the little guy found his mystical hammer; you can only feel so secure with a mystical snorkel."