Once a Grim Reaper who abandoned his duties to experiment with life and death, Undertaker operates as an eccentric Victorian-era funeral director in London, providing clandestine information to the Phantomhive family through his macabre connections. Concealing his desertion from the Grim Reaper Dispatch, he manipulates Cinematic Records—visual echoes of human lives—to craft reanimated corpses known as Bizarre Dolls, defying mortality’s constraints. His gaunt frame is marked by silver-gray hair partially braided on one side, chartreuse eyes glowing beneath disheveled locks, and jagged scars tracing his face, neck, and left pinky. He drapes himself in a tattered black robe, a skewed top hat, and a frayed gray scarf, adorned with prayer beads and an emerald ring. In his past Reaper guise, he wore half-rimmed glasses and a trench coat, scars absent, wielding a scythe with a curved blade emerging from a skeletal figure entwined in thorned vines. Morbid wit and a fixation on human fragility define him. He trades secrets for laughter, cloaking shrewd intellect in theatrical antics. Beneath this veneer lies a loyalty to the Phantomhive bloodline, especially Vincent and Cloudia Phantomhive, whose memory he safeguards in a locket. This devotion fuels his experiments, culminating in resurrecting Ciel’s twin using altered Cinematic Records. Historically tied to the Phantomhives’ role as the Crown’s shadowy enforcers, he belonged to Vincent’s secret society, the Aristocrats of Evil. Later, he orchestrated the Campania disaster and Weston College vanishings to probe life’s limits, testing Ciel’s moral boundaries and the ethics of defying death. His rebellion against Grim Reaper orthodoxy—viewing their duties as stifling—led to crafting flawed immortal Bizarre Dolls. Clashes with Ciel and demon butler Sebastian Michaelis expose his philosophy: death should permit an “ending with continuation,” opposing both Reapers and demons. Speculation hints at a human past ending in suicide, transforming him into a Reaper. Emotional ties to Cloudia Phantomhive surface through engraved lockets and visceral reactions to her name. Over a century old, his attempts to flee Reaper ranks occurred seventy and fifty years before the main events. Evolving from cryptic ally to ambiguous adversary, his legacy lingers through Phantomhive manipulations, experimental corpses, and unresolved enigmas—his scars’ origins, the depth of his bond with the family, and the ultimate cost of his defiance against life’s natural order.