Jonathan Joestar, the protagonist of the first part of the popular manga and anime series "JoJo's Bizarre Adventure," is known for his strong and honorable personality. He embodies many classic heroic traits, including unwavering determination, a strong sense of justice, and a deep loyalty to his family and friends. Jonathan is courteous and chivalrous, always striving to do what is right. He can be somewhat naive at times, but he has the purest of hearts.