Towa Higurashi is the firstborn fraternal twin daughter of the full demon Sesshomaru and the human Rin, born during a lunar eclipse in the feudal era. Separated from her twin Setsuna at age four during a forest fire set by the demon Homura under Zero's command, Towa plunged through a temporal portal to modern-day Japan. Sota Higurashi, Kagome's younger brother, found and adopted her. Raised in Tokyo by Sota, his wife Moe, and their daughter Mei, Towa grew up peacefully but faced frequent bullying due to her demonic traits. This led to a rowdy personality, engaging in fights while consciously restraining her strength to avoid injuring humans. She experienced loneliness and guilt over losing Setsuna, especially during milestones.

Her personality reflects a duality shaped by her upbringing. In the modern era, she displayed a protective, anti-bullying stance and athletic prowess, winning track and martial arts trophies. Reunited with Setsuna a decade later in the feudal era, Towa adopted a pacifist approach, refusing to kill sentient beings unless absolutely necessary—a value instilled by Sota. This contrasted with Setsuna and their cousin Moroha (Inuyasha and Kagome's daughter), who viewed her reluctance as naive. However, Towa exhibited fierce protectiveness, especially toward Setsuna, and could turn vengeful when provoked, confronting Homura or Kirinmaru after he killed Setsuna. Subtle dog-demon behaviors included lapping water from streams, shaking off water post-battle, and a kneeling posture reminiscent of a canine sit.

Physically, Towa has silver hair with a distinctive "paradise pink" streak in one bang and magenta eyes. In the feudal era, she wears a modified male school uniform: a white blazer with violet accents, graphite dress shirt, red ribbon tie, white pants, and brown boots for combat mobility. During new moons, she transforms into a full human with shoulder-length black hair and brown eyes. Her full demon form, activated under extreme emotion or will, features a violet crescent moon on her forehead (inherited from Sesshomaru), red cheek markings, elongated claws, pointed ears, pronounced fangs, and a bright sky-blue energy aura. When enraged and uncontrolled, her eyes shift to teal slits with red sclera, and her aura turns crimson.

Towa wields the demonic sword Kikujumonji, initially a replica that shattered in battle but later reforged into a genuine weapon. She channels her demon energy into the blade for energy-based attacks. After Setsuna's temporary death, Towa used shattered Tenseiga fragments to revive her, leading to its reforging into Yukari no Tachikiri, capable of severing threads of fate. She later acquired the cosmic sword Zanseiken from Rion, Kirinmaru's daughter. Innate abilities include absorbing demonic energy (yōki), Sesshomaru's poison resistance, and enhanced strength. A Silver Rainbow Pearl embedded in her left eye granted amplified power, though she later gifted it to Riku, Kirinmaru's incarnation. Her direct, aggressive combat style forgoes evasion, leaving her vulnerable to counters.

Her character arc centers on relationships and trauma. Profound guilt over releasing Setsuna's hand during the fire drives her obsession to restore Setsuna's stolen dreams and memories via the Dream Butterfly. This strains their reunion, as Setsuna initially doesn't remember her and resists Towa's overprotectiveness. Towa viewed Mei as a substitute for Setsuna during their separation, reinforcing her familial loyalty. She allies closely with Moroha, sharing a playful, supportive dynamic. Interactions with Riku involve romantic tension; she blushes at his advances and trusts him enough to give him her pearl, regretting it upon discovering his allegiance to Kirinmaru. She eventually differentiates Riku and Rion from Kirinmaru's actions, maintaining friendships despite her hatred for Kirinmaru.

Towa's development spans key events. Her initial quest focused on locating the Dream Butterfly for Setsuna, leading her to permanently return to the feudal era. After Kirinmaru killed Setsuna, Towa awakened her full demon powers, vowing revenge and wielding Tenseiga to resurrect her sister. Setsuna's recovered memories and apology resolved Towa's longstanding guilt. Towa confronted Zero, whose "Silver Scale Curse" linked her life to Rin's; in a rage, Towa nearly killed Zero despite the risk to Rin, requiring intervention from Riku and Setsuna. During the battle against Kirinmaru and the Grim Comet, she traveled to the modern era to destroy the comet, sacrificing her ability to return to the Higurashi family. The series concludes with her reunited with Rin and accepting her role alongside Setsuna and Moroha. In manga continuity, she expresses attraction to women, wears a female school uniform, and demonstrates greater willingness to kill demons, partly due to assisting the Higurashi family with exorcisms.