Hildiculous
When something is just so utterly ridiculous and inconceivable, it could only have been pulled off by an incredibly drunk girl, probably with a name like Hilary or Hilda.
Me: "Damn, did you see that girl on the dance floor? How did she even pull off that move, that makes no sense?"
Friend: "Yeah dude, that was straight hildiculous, my mind is blown."
Friend: "Yeah dude, that was straight hildiculous, my mind is blown."