Emberr

Hello, so i just came into Mauville for the first time and i saw a NPC named Valak that stood in front of the sign in the image when i interacted with it it said something like "GRRRRRRR" and then it vanished. I went searching on the internet but there wasn't even a single thread about it and in discord nobody had heard about it so i was wondering what it was about is it some sort of Easter egg Etc. PS i have seen the conjuring movies so that's why i was wondering anyway thanks for answering if someone knows.