Tsukihiko found himself in the midst of an assassination attempt on a young girl named Sami six years ago. Despite his efforts to shield her, the two were gravely injured in the attack. However, Sami came from a wealthy and powerful family who were able to use their vast resources to save their lives by converting their bodies into cyborgs. Unfortunately, this resulted in Sami having to permanently rely on a wired connection to a life-sustaining computer. On the other hand, Tsukihiko embraced his new form and became a "Knight" cyborg, pledged to protect Sami from any future threats.
