Sumire possesses a cheerful, helpful, and lighthearted demeanor, which Nene notes closely resembles Aoi’s personality. She appears kind and accommodating at first, but beneath this exterior lies a manipulative and almost sadistic side. This is evident in Chapter 89, where she is shown caring for wounded animals not out of compassion, but because she enjoys having complete control over them. Her fixation on controlling others extends to Nene and Hanako, whom she refers to as “lost raccoons” and wishes to keep as her personal pets. To ensure they remain under her care, she sets up electrified barriers around her home to prevent escape and forces Nene into doing household chores.

When first encountering the mountain villagers, Sumire displays a cold and indifferent demeanor, showing little concern for their presence in her sacred garden. Her authoritative status is evident, as the villagers immediately bow in her presence, indicating that she holds a position of power among them. However, her true allegiance is unclear, as Hanako suspects that she is following No. 6’s orders.

In her past memories, Sumire served as a kannagi (shrine maiden) for sacrifice, a role she accepted in hopes of fulfilling her duty. However, in the present timeline, she attempts to substitute Nene as the new sacrifice, hoping that doing so will elicit a reaction from No. 6.

As revealed at the end of Chapter 66, Sumire is in love with No. 6, which adds complexity to her actions. She compares her situation to Nene’s, recognizing that loving a supernatural is a taboo and acknowledging the tragic nature of her feelings.

Sumire has long black hair, though in some of AidaIro’s illustrations, her hair appears reddish-brown, resembling Aoi’s hair color. She has pale blue eyes and fair skin, giving her an elegant yet haunting appearance.

Her kimono is a pale lavender with magenta hues and features flower patterns on the sleeves, as revealed in the September 2020 color spread. She wears a deep red obi, along with traditional zori sandals and plain tabi socks. On both wrists, she wears bracelets adorned with bells, which she claims are protective charms. She later gives one of these bracelets to Nene as a form of protection.

Notably, Sumire bears a talisman that closely resembles Tsukasa’s seal, though their placements differ hers is located on the side of her neck, while Tsukasa’s is on his right cheek. The significance of this resemblance remains unclear but hints at a deeper supernatural connection between them.

In flashbacks of her childhood, particularly a scene where she is hiding in a cave with No. 6, Sumire is depicted wearing a large hair bow and a kimono similar to her current one. This kimono is magenta-hued and features sky blue accents, including a blue bow tied at her waist and white-blue floral patterns on the ends of her sleeves.

In Chapter 62, an unusual spirit resembling Sumire appears, leading Nene and Akane to an elevator. This ghostly figure has concealed eyes and speaks in a sing-song tone about No. 6 and his yorishiro. Her clothing drifts behind her as bright particles float around her, creating an ethereal effect. It remains uncertain whether this apparition is truly Sumire’s spirit or merely an illusion tied to No. 6’s boundary.

Sumire was born in a village located near a cliff, which was rumored to lead to the Far Shore. At the age of six, she was offered as a sacrifice, a fate determined by her family and the villagers due to the Akane bloodline’s connection to the supernatural.

While crying near a cluster of Jizo statues, Sumire expressed sadness over never having seen her parents’ faces and being completely ignored by the villagers. Even her own family distanced themselves from her, as shown in Chapter 70, where they stood far away from her in a family photograph. Her only caretaker was No. 6, who watched over her under his master’s orders to ensure she wouldn’t escape while she awaited her fate as a sacrifice.

Despite the circumstances, Sumire grew attached to No. 6, affectionately referring to him as her “husband” and acting as a housewife, cooking for him and caring for his well-being. Though she openly expressed affection for him, No. 6 did not reciprocate her emotions. The two often ventured outside together, and one of Sumire’s earliest memories was seeking shelter in a cave during a rainstorm, where she asked if No. 6 would always be there for her.

Sumire never outwardly despaired over her fate as a sacrifice. When the time of her sacrificial ritual approached, she prayed to the Jizo statues, wondering if a new statue would be made in her honor once she was offered to God. However, after becoming a yorishiro, she finally witnessed the truth the Far Shore was never a place to be near God, shattering her prior beliefs about the meaning of her sacrifice.

The village where Sumire once lived was eventually destroyed, and Kamome Academy was built on its remains, connecting her past directly to the supernatural mysteries of the present.

Lightning
Sumire possesses the ability to manipulate lightning, similar to Teru Minamoto’s lightning cage. She uses this power to create a barrier around her home, which effectively prevents Nene and Hanako from escaping. Additionally, she can stun Hanako with a mere flick to his forehead, demonstrating her control over electrical energy. In one instance, Hanako is seen unconscious near Sumire, while her blade crackles with lightning, suggesting that she can also imbue weapons with her power.

Seeing Supernaturals
Sumire has been able to see supernatural beings and apparitions since childhood. This ability played a key role in her initial interactions with No. 6, as she could recognize him and communicate freely. Additionally, she playfully gives Hanako a new nickname, “Gon”, showcasing her ease in interacting with spirits.

Yorishiro
As revealed in Chapter 68, Sumire explains that being a yorishiro means she is trapped in a cycle where time rewinds upon her death. She refers to this endless loop as a “prison of time”, in which she is forced to relive her final day and wedding ceremony repeatedly. Despite her devotion to No. 6, she never once saw him visit her after she became a yorishiro, leaving her isolated in a constant state of death and rebirth.

Akane Sumire’s character represents sacrifice, fate, and the supernatural burdens passed down through generations. As someone born into a family whose children are offered to supernatural forces, her existence raises questions about the true nature of the Akane bloodline and its connection to Kamome Academy’s mysteries.

Her role in the supernatural hierarchy remains mysterious, but with Nene and Teru acknowledging her significance, she is likely to become a key figure in the unfolding supernatural events at Kamome Academy.