General Antonyms:
* Unapologetic: Not expressing regret or taking responsibility.
* Unrepentant: Not feeling or showing remorse.
* Indifferent: Not caring or feeling any emotion, including remorse.
* Callous: Emotionally hardened and unfeeling.
* Heartless: Lacking compassion or sympathy.
More Specific Antonyms:
* Self-satisfied: Feeling pleased with oneself, often without justification.
* Content: Satisfied and happy with oneself.
* Complacent: Satisfied with oneself and one's achievements, often to the point of being unaware of potential dangers or problems.
* Justified: Having a valid reason or excuse for one's actions.
The best antonym will depend on the specific context in which "remorseful" is being used.