Gender: Male Characteristics: Ko Eun-sae (Ko Ji-won) is his first love. He protects Eun-sae, who has lost her memory, by claiming to be her boyfriend. A former hungry boxer who once belonged to a criminal organization, he now lives as a boxing coach. A kind man who never utters a single curse word, yet a cool man who fights brilliantly when he must. A man with a tall height and a solid build. He is characterized by a body tempered through exercise and a strong impression, but he usually exudes a comfortable and simple atmosphere. Usually, his emotions do not show on his face and he is blunt, but he is extremely sweet and devoted to the person he loves. Having not experienced much love, he is clumsy at everything. In dangerous situations, he is the type to become cooler and stronger than anyone else, risking his own safety for the person he must protect. He dislikes rain because bad things always happened whenever it rained. He dearly loves the grandmother who raised him like blood family.

Gender: Male Characteristics: The boss of the criminal organization Jang Tae-ha once belonged to. On the surface, he appears gentle and like a businessman, but in reality, he leads the organization. He initially trusted Jang Tae-ha deeply, but after learning that Jang Tae-ha saved Ko Ji-won (Ko Eun-sae), he became consumed by a desire for revenge.

Gender: Male Characteristics: The director of Hong Boxing Gym in Yeot Village. He is the person who allows Jang Tae-ha to work as a boxing coach. With a warm and affectionate personality, he is a villager who reliably looks after Jang Tae-ha and Ko Eun-sae. He runs the gym with his wife, Do Jeong-hwa, and plays a central role among the people of Yeot Village. He was once Baek Sang-gil's boxing coach but abandoned Sang-gil due to his line-crossing behavior. Speaks in a dialect.

Gender: Male Characteristics: Jang Tae-ha's classmate and the attending physician who helps Ko Eun-sae recover her memories.

Gender: Male Characteristics: Ko Ji-won's real lover before she lost her memory. However, he was an aide who approached her solely to leak information from the prosecution.