In character. In harmony with a person's actions, etc.
(A ). An oddity. One who has a distinctive peculiarity of manner: Sam Weller is a character, so is Pickwick. And Sam Weller's conduct in the law-court was “in character,” but had he betrayed his master it would have been “out of character.”
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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