As a child, Shion Pavlichenko once went stargazing with his twin sister Suou and their father, Dr. Mikhail Pavlichenko. During the outing, Shion noticed a series of shooting stars falling in quick succession. One of these “stars” eventually crashed near their campsite. Suou believed this incident marked the moment Shion became a Contractor. However, it is later revealed by Mikhail that Shion had always been a Contractor, even before that event.

While visiting the university where their father conducted his research, an explosion occurred. The blast killed Suou and rendered their mother, Asako Makimiya, unconscious. Upon awakening, Asako searched for her daughter, leaving Shion alone outside. When she returned, she saw Shion waving to her from a window inside the building. Following this, Shion remained with Mikhail, while Asako left the country with Suou’s remains.

As a Contractor, Shion exhibits the typical emotional detachment associated with his kind, often struggling to grasp ordinary human emotions. He attempts to understand them through a rational, scientific perspective, though with limited success. Due to being physically disabled and largely confined to his home, Shion relied on his twin sister, Suou, to bring him glimpses of the outside world through her photography, a possible reflection of his desire to connect with life beyond his isolation.

Despite his seemingly cold demeanor, Shion displays a strong attachment to Suou and interacts with her kindly. His relationship with their mother, however, appears distant, marked by indifference. His father, Mikhail Pavlichenko, deliberately limited Shion’s contact with others due to his Contractor nature, even cautioning Suou to keep her distance. Nevertheless, Shion is highly perceptive and aware of events around him.

His deep affection for Suou becomes evident when he creates an entire world for her and insists on calling her his sister, despite her being a copy. He even kills Tanya Akulova, another Contractor, to protect Suou, an action suggesting that, despite his Contractor identity, his bond with Suou transcends logic.

Shion is a young boy with striking red hair and vivid green eyes. He is often seen with a bandage covering his right eye and part of his forehead, suggesting a past injury or medical condition. Due to his physical disability, Shion typically uses a wheelchair for mobility. His usual attire consists of pale green pajamas, reflecting both his reclusive lifestyle and the clinical environment in which he is often confined.

Duplication
Shion possesses the ability to create near-perfect duplicates of objects, people, and even entire environments. These copies are virtually indistinguishable from the originals but contain one inherent flaw. The exact scope of his power remains uncertain, but notable applications include replicating his father, Suou (as a separate identity), and even crafting an alternate version of Earth devoid of Contractors or Dolls. Shion also appears capable of manipulating aspects of his creations with precision—for instance, embedding fabricated memories in the clone of Suou, limiting his father’s clone to 24 hours of memory, and shaping entire realities according to his intent. In one instance, he seemed to communicate telepathically with Suou, though it is unclear if this was an implanted memory designed to activate under specific conditions.

Obeisance
As the cost of using his Contractor ability, Shion loses the use of his legs each time his power is activated. As a result, he is permanently reliant on a wheelchair.

Marksmanship
Similar to his sister, Shion has demonstrated skill in handling firearms, particularly an anti-tank rifle resembling the PTRD-41. Though the origins of his training are not explicitly shown, it is implied that he may have been instructed in hunting by his father. Unlike Suou, Shion is left-handed, which subtly distinguishes the two.