Derived from the question regarding the identity of the person within Sixth Edo Tensei Coffin summoned by Kabuto Yakushi in the Naruto Manga, which appeared to gain a significant reaction from the normally unshakable Madara Uchiha, which has started a rampant stream of theories and suggestions for the interest of speculation.

Can be seen and referred to also as a plot device where the appearance of any unseen/unknown character whom holds some key significance to the story, by causing a shocked or emotional reaction/outburst in an important/major character.
Abridged Version of Conversation

Madara: You want to join forces with me?
(Kabuto summons five coffins with Edo Tensei, which are the deceased Akatsuki members)
Madara: What do you want in return?
Kabuto: Uchiha Sasuke.
Madara: What if I say no?
(Appears Kabuto's Sixth Coffin)
Madara: Th-That's...! You madman! How did you do this?!
Kabuto: Oh you know... Anyway, you can relax. I haven't told a soul.
by Purple Ram September 10, 2010
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