Hinata Mukai is a character who appears exclusively in the original video animation episode of Deadman Wonderland, titled Red Knife Wielder. She is an original character not featured in the main storyline of the series. Hinata is a young woman in her late twenties who serves as the caretaker for a group of orphaned children, including a boy named Izuru. Her background is tied to a catastrophic earthquake known as the Great Quake, which she herself survived. The trauma and loss caused by this disaster shaped her entire life afterward, as she dedicated herself to helping children who lost their parents to the same calamity by opening her home to them. Physically, Hinata is depicted as a slender woman with short black hair that covers her ears and most of her forehead, along with gray eyes. Her attire consists of a long, hooded dark blue overcoat with white stripes on the sides, complemented by yellow boots and light blue gloves.

In terms of personality, Hinata is characterized by her deep compassion and nurturing nature. She is known to take in any orphan from the streets, providing them with shelter and food without hesitation. However, her kindness is balanced with a streak of strictness or harshness when the situation calls for it, as shown when she smacks Izuru without warning for his misbehavior. Her motivations are rooted in a sense of revenge against the earthquake and the destruction it caused. She does not view her altruistic work as simple charity but rather as an act of defiance and retribution against the disaster that took so much from so many.

Within the story of the OVA, Hinata plays a supporting role that is deeply connected to the character Senji Kiyomasa, also known as the Red Knife Wielder. She shares a close bond with Senji, and they interact as friends who speak with ease and familiarity. Senji compliments her on her care for the children, further highlighting her dedication. Her relationship with Senji is a significant part of her narrative, and while never explicitly stated, it is implied that she may hold romantic feelings for him. The central conflict of the OVA begins when Senji returns Izuru to her after the boy stole from a gang called the Goreless Peace. This gang later starts a fire at her home as a means to force Senji to join them. Tragically, Hinata is killed in this fire, marking her demise as a pivotal event that drives Senji's actions. Her development is limited to the OVA's runtime, but she is presented as a fundamentally good and caring person whose life was defined by tragedy and whose death serves as a catalyst. No notable supernatural abilities or combat skills are attributed to her; her role is that of a civilian caretaker rather than a fighter or a Deadman.