Apachai Hopachai is a Muay Thai master of the Ryōzanpaku Dojo, known as the God of Death in underground fighting circles. His childhood was marked by turmoil, including being trafficked to a crime syndicate and later unwittingly serving criminals involved with child trafficking. Rescued by Agaard Jum Sai, he trained at Romtyphoon Gym and became a lethal fighter capable of felling opponents with a single strike. Despite his deadly skills, Apachai has a childlike and naive personality, showing deep affection for children and animals. He struggles to moderate his strength due to survival instincts and language barriers, sometimes unleashing fatal force unintentionally. He interjects “Apa” into his speech and once answered phones with hostage threats, echoes of his darker past. His martial arts mastery includes Muay Thai and the ancient Muay Boran, which he practices secretly to shield his disciple Kenichi Shirahama from its most lethal techniques. Apachai possesses extraordinary physical abilities, such as leaping great distances, pulverizing stone, and surviving mortal wounds through sheer will. He has a paralyzing fear of airplanes rooted in trauma and can be gullible. Over time, he learns to temper his power, treating Kenichi as a cherished child, and finds joy in simple accomplishments like mastering laundry. His journey from a weaponized killer to a guardian is marked by pivotal battles, including a duel with Agaard, and his bonds with friends like Honoka Shirahama.