The most devastating deaths in anime do more than simply remove a character; they shatter the established world, forcing companions to mature and heroes to confront their mortality. These moments can divide fanbases or unite them in shared grief, serving as powerful catalysts for catharsis and narrative evolution. The 21st century has delivered several such shocking fatalities that left indelible marks on their series.

Honorable Mention: Satoru Gojo (Jujutsu Kaisen)

While yet to be adapted into the anime, the death of Satoru Gojo in the Jujutsu Kaisen manga sent shockwaves through its fandom. His demise was so impactful that a real-life memorial was held in Chile. Gojo's status as "the strongest" made his unexpected end in his prime particularly jarring. His absence, even temporary through sealing, collapsed the existing jujutsu society, creating a crisis of civilization and instilling a sense of hopelessness. The realization that even the most powerful figure could be so easily defeated by Ryomen Sukuna dramatically altered the narrative's trajectory and cast doubt on the survival prospects of younger sorcerers like Yuji Itadori.

David Martinez (Cyberpunk: Edgerunners)

The Cyberpunk: Edgerunners anime, a prequel to Cyberpunk 2077, offered a bleak outlook with few traditionally happy endings. Protagonist David Martinez's journey from humble beginnings to legendary edgerunner was underscored by his relentless use of an experimental cyberware implant, the Sandevistan, pushing his body to its limits. Despite setbacks and casualties within his crew, there remained a hope that David's resolve would see him through Night City's harsh realities. This hope was brutally extinguished by Adam Smasher, Arasaka's cybernetically enhanced mercenary. David's death, before he could fulfill his dream of going to the Moon with his lover Lucy, reinforced the franchise's themes of lost innocence and the futile pursuit of exceptionalism in a cruel society.

Portgas D. Ace (One Piece)

Eiichiro Oda's One Piece, known for its infrequent character deaths, presented a particularly disorienting loss with Portgas D. Ace. After his capture, Monkey D. Luffy undertook a perilous mission to rescue him from Impel Down, making Ace's subsequent demise feel unjust. Provoked by Admiral Akainu's insults, Ace impulsively engaged the powerful marine, leading to his fatal encounter where Akainu's magma fist pierced him. Ace's death marked a significant turning point, forcing Luffy to confront the world's unpredictable nature and mature from naive optimism to a more hardened warrior. This event necessitated a shift in the Straw Hats' expectations as they prepared for the challenges of the New World.

Nina Tucker (Fullmetal Alchemist: Brotherhood)

The Fullmetal Alchemist: Brotherhood narrative includes many horrific moments, but the encounter with Shou Tucker and his daughter Nina stands out. The Elric brothers bonded with the cheerful Nina and her dog Alexander, only to discover Shou's depravity when he used alchemy to transmute them into a Chimera. This shocking transformation, a grim demonstration of the recklessness of State Alchemists, left Nina and Alexander in unimaginable pain. Their existence was mercifully cut short by Scar, but the event underscored the vulnerability of even the most innocent lives. The tragedy highlighted that no one was safe, not even a child betrayed by her own father.

Mayuri Shiina (Steins; Gate)

Steins;Gate subverts typical time travel tropes, initially presenting Rintaro Okabe as a quirky character. His childhood friend, Mayuri, is depicted as a sweet and loyal companion. Mayuri's repeated death, initially in cold blood, shatters Rintaro's world and becomes the focal point of his desperate attempts to alter timelines. Her death is portrayed as an inescapable event, central to the story's exploration of time manipulation's consequences. Mayuri's warm presence grounded the narrative, and her loss destabilized the sense of safety, forcing Rintaro to endure endless tragedies in his quest to correct his errors. Her eventual survival is hard-won, making the anime's conclusion emotionally resonant.

Kamina (Gurren Lagann)

Gurren Lagann, a series celebrating human will, tragically kills off its deuteragonist, Kamina, early in its run. Kamina, established as a foil to the anxious Simon, created an illusion of an unstoppable duo. Their contrasting personalities—Kamina's bravado versus Simon's anxiety—were mutually reliant. Kamina's death, occurring after a victory against the beastman Thymilph, left Simon to confront his limitations and temper Kamina's boldness with pragmatism. Despite his outward confidence, Kamina harbored unspoken fears, making his demise more poignant. His death robbed the story of its immediate optimism, leaving Simon and the others to rally from this significant setback, ultimately becoming stronger through confronting their grief.