It goes against my grain to be running around the courts for justice

Character : the mental and moral qualities distinctive to an individual.
Eccentric : (of a person or their behaviour) unconventional and slightly strange.
Training : the action of teaching a person or animal a particular skill or type of behaviour.
Personality : the combination of characteristics or qualities that form an individual's distinctive character.
Grain : a person's character or natural tendency.

Synonym of Grain is Personality