Kang Shi-chan is an ace high school student and a top model. After a celebratory drink with his cram school teacher, he runs across a talking dog that urgently tells him to run away. Too startled to immediately obey, Kang Shi-chan watches as a strange man appears chasing the dog. After saying something about an "emperor" and "Inferno", the strange man transforms into a monstrous creature and attacks - nearly killing Kang Shi-chan in the process. The dying dog offers a desperate plea to save them both and Shi-chan accepts, changing his life forever.
Kang Shi-chan has an arrogant personality as an amazing student with a professional modeling career. He's extremely confident in his ability to woo women, and appears to have something of an interest in older women like his cram school teacher. Nevertheless, he does seem to prefer not to hurt people and would even risk his life to save innocent bystanders. Shi-chan also possesses an exceptionally strong will to live, which allowed Inferno to possess him without killing him. He also processes new situations quickly and surprisingly calmly, even when his life is in danger and he is terrified.
As the host to Inferno, Kang Shi-chan has superhuman strength and incredible recovery abilities, as long as his heart is intact. His strength is limited by the amount Inferno can corrode him without killing him, as high corrosion will transform him completely into Inferno's tedlar host and kill Shi-chan. He also has access to Inferno's spells based on how many Invento Hells he possesses. Later on, when he reaches around 30% corrosion, he gains access to Inferno's legendary Blue Flames of Destruction.