Haha it's just a catchall term I use for general slenderfuckery. It's referring to the waveyness of his arms.

And...well, that's...hm. I'd say that long term contact with Slendy causes long term memory loss, but that's really too godmodey for me to bring to the mansion for anyone except the MH cast if they want it. Short term contact with slendy is short-term memory loss. So like...you meet Slendy, you forget meeting him, and maybe a few hours in the vicinity as well. Going for up to a week or two at the very tops, but I wouldn't wipe her canon memories.

Did...that make sense?