pretty much everytime i wanted to search for sonic the hedgehog stuff on google as a kid i would find weird/creepy stuff instead
one time i was looking for dark super sonic pictures, and when i found a cool one for some reason instead of giving me the actual image it gave me bondage special interest fanart that looked like it was made in ms paint.
then there was a newgrounds flash animation where sonic needed to find a costume for a halloween party before it was too late. he eventually finds a store, runs fast towards it, but it closes down in his face. then tails appears and jokes about how sonic couldn't get a costume, only for him to get skinned alive by sonic with really loud horror music that nearly gave me a heart attack, ending with sonic appearing on knuckles' house wearing the skin of tails.
and then there's the whole tails doll creepypasta thing and deviantart, should be self-explanatory