Winner is the first to give the correct answer.
Q: This tattoo was made famous by WHAT populer TV series?
Bonus: According to the show's lore what does this tattoo do?
A: Supernatural
Bonus: It keeps them from being possessed by Demons.
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Winner: Shadowbanes -One Point-
Bonus Winner: No one.
Insanctuary
This is the symbol of the perpetual state we call, the sun-moon-star-circle-dance. It is the following elements of life and death, which have been aligned in one form to represent the oneness of the greatness that is life.
wyldfyre1 (Updated )
You actually gave a response that was more fact. The question itself was about the tv series and what it has to do with the series =). Though thanks to you i have learned something today