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-Kuudere characters in simple... words?

"Kuudere" is a combination from "Kuu-" and "deredere", a Kuudere character, is one that while at first glance it might look like a silent, cold, and sometimes even emotionless person, after the character develops and the story goes on, it will, in most cases, appear now as a caring, good, heartwarming person.

Some examples might be:
Rei Ayanami (Neon Genesis Evangelion)
Yuki Nagato (Suzumiya Haruhi no Yūutsu)
C.C. (Code Geass)
And the list goes on.