Provide a comprehensive overview of Sung Jin-woo, the main character from the webtoon "Solo Leveling." Include information on his background, character development, abilities, key plot points, and the journey he undertakes throughout the series. Additionally, discuss how his character evolves from being a low-ranked hunter to one of the most powerful beings in the world. Be sure to touch on the following key elements: - Initial status as a weak hunter - The awakening process and the significance of the "System" - Major battles and adversaries he faces - Relationships with other characters - Themes represented through his journey, such as determination, resilience, and growth.