This Supernatural photo contains
bouquet, corsage, posy, nosegay, and business suit.
There might also be
fire, flames, inferno, japanese apricot, mei, prunus mume, sign, poster, text, and chalkboard.
After Dean discovers and confronts Sam on his blood-addiction, Castiel confides in Dean the secret of the last seal. This is why Dean then contacts Sam, and is so panicked when it doesn't work.
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