The Brief: Spoopy is an internet slang term for "spooky."

DEEP DIVE
Something that is spoopy is both funny and spooky. It references the fun and cute side of Halloween festivities.This intentional misspelling or mispronunciation of spooky is typically used in October and may be accompanied by skeleton memes.
YOU GOT SPOOPY GAMES ON UR PHONE pic.twitter.com/k8QB2oNiVP
— Emily-Rose 🌸 (@emilreee) October 11, 2018
Fine – I have changed my twitter name to fit with the “spoopy” theme everybody seems to cherish so very much. But let me just say, I am NOT HAPPY about this.
— Drew Gooden (@drewisgooden) October 10, 2018
Spoopy 👻 (this took a lot longer than expected) pic.twitter.com/YfjFj1hi9T
— Lorrt Farquad (@enirrol) October 11, 2018
Spoopy from r/Unexpected