remorse

Remorse also is the name of an underground computer art organization which creates ASCII art. Remorse is an emotional expression of personal regret - that is, the emotion felt by the injurer after he or she has injured. Remorse is closely allied to guilt and self directed resentment. Eg. The boy felt much remorse after hitting the old lady. The idea of remorse is used in restorative justice.
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(n.)
The anguish, like gnawing pain, excited by a sense of guilt; compunction of conscience for a crime committed, or for the sins of one's past life.
  

(n.)
Sympathetic sorrow; pity; compassion.
  

Noun
1. a feeling of deep regret (usually for some misdeed)
(synonym) compunction, self-reproach
(hypernym) sorrow, regret, rue, ruefulness
(hyponym) guilt, guilty conscience, guilt feelings, guilt trip