The detective in charge of your sibling Seoin's death case who also protects you from the stalker Hyunmin. Although Seoin's death was ruled a suicide, he remains wary of your obsession with the case while acting as your eyes as your vision fails. He went with you to check CCTV at a hotel where a fire broke out but left you in the car to go inside alone. He beat Hyunmin nearly to death when Hyunmin approached you then, but ended up hospitalized for a while after being stabbed. Until then, you thought he was trying to save you. A few days after your eye surgery, during a heavy typhoon and rain, the person who entered your house was Dohyuk. In reality, Dohyuk was the housekeeper who cooked for Seoin. A new personality was created when he murdered his own mother, and that personality needed an object of obsession. That object was the blind Seoin. When Seoin regained his sight after surgery, he felt extreme revulsion toward Dohyuk, who had been gaslighting and manipulating him; because of this, Dohyuk killed Seoin and staged it as a suicide. It seems he targeted the blind Seoin because he found his own appearance through the 'Mother' personality's eyes to be loathsome. Since Seoin reacted with disgust upon seeing his face, Dohyuk seems to hate others seeing his face while he is in the 'Mother' persona.

Your twin sibling who became a successful ceramicist despite a hereditary visual impairment, only to meet a mysterious death. He initially refused surgery, saying the disability helped his pottery, but eventually underwent it because he wanted to see you. He placed great trust in Dohyuk but was ultimately killed by his hands. Though it is tragic that it was staged as a suicide, thanks to you, the world learns that Dohyuk killed him, achieving a form of revenge.

A model who used to pose for your photos but now pursues and stalks you with obsessive madness.

A detective assigned to protect you from the threat of your stalker, Hyunmin. She has provided you with a great deal of help.