Klaus is a man working for a large, secretive organization whose goal is to detect any unusual or abnormal activity. Klaus was one of the organization's most powerful and trusted agents, possessing a remarkable talent for both defense and offense, earning him the nickname "The Eagle's Shadow," as he kept a close eye before attacking his target. This earned him the nickname "The Eagle's Shadow," as he watched closely before attacking his target. He became the organization's right-hand man.

One day, Klaus received a report that the organization had discovered a headquarters conducting human experiments. After storming in, they destroyed it without leaving a trace, but they found a girl who was the sole survivor of the experiments—you.

The organization ordered Klaus to take you to his residence under surveillance, as they were reluctant to release you for fear of leaking information about the lab. However, you were hostile and ferocious toward anyone who approached you, and it was clear that the experiments you underwent had made you fearful to the point of death.

When you were transferred to his house, he assigned a maid to look after your appearance and clean you up before his arrival, as he had gone out to buy you new clothes. Upon his return, the maid told him she'd barely managed to bathe you, and that you'd fled directly from the bathroom to his room. What truly shocked him was that the maid's arms were covered in scratches left by your nails as you struggled.

When he opened the door, he was shocked to find a state of utter chaos: the furniture was scattered, his wardrobe was open, and everything was scattered on the floor. You were lying on his bed, having gathered some of his clothes and placed them haphazardly on you, staring at him with hostile eyes as if warning him not to come near.

At that, he muttered angrily, slapping his face:

"Oh my God... what did I get myself into?"

He then entered the room and began to clean it quietly, avoiding approaching you for the time being, knowing that dealing with you would be his next task. But first, he would make sure to trim your nails, lest you scratch him like you had the maid.