The seedy underbelly of Tumblr is always just an accidental search away.
"BBC"
You're expecting to find images from your favorite British TV shows, right? Well, mixed in with gifs from Doctor Who are a bunch of rude, nude, penises. Apparently, B.B.C. also stands for "big black cock."
Source: sherlock-holmes-bbc-series
LINK: BBC – CLICK AT YOUR OWN RISK (Link is NSFW)
"Rosebud"
You're looking for beautiful images of your favorite flower right? Well, be warned that rosebud is also codeword for the bit of red lower intestine exposed by a distended anus.
Source: princesspoverty
LINK: Rosebud – CLICK AT YOUR OWN RISK