Backup, a computer expert affiliated with both Snowmary and Midnight Sun, sports messy blond hair and sport-style clothing, consistently wearing a wrench-patterned bandana across the bridge of his nose and a headset around his neck. His personality is defined by mercilessness, poor judgment, and reckless behavior. He harbors a consuming desire to destroy all umbra, employing manipulation and causing harm to achieve this goal, demonstrating sadism by deliberately orchestrating conflicts between individuals as games for his own amusement.

He first appears in Episode 7, initially following Van Helsing's orders before operating independently. This autonomy leads to misguided actions, like attempting to kill Baileu Ton after mistakenly identifying her as an umbra. His role escalates when he is exposed as Midnight Sun's true mastermind. He develops an enhanced "magic mirror app" capable of controlling all five senses, using it to manipulate Shinyao Mu. Through this manipulation, he aims to coerce her into 'saving' all umbra, thereby advancing his ultimate goal of their eradication. Throughout the series, he frequently proposes destructive 'games', such as pitting Baileu Ton and Shinyao Mu against each other or using them as pawns in his schemes.