Why Does Nacht Hate Yami?
Nacht's hostility toward Yami is rooted in guilt over Morgen and his own forbidden devil ritual. See why Yami is a reminder of that past, not its cause.
Nacht does not hate Yami because Yami killed Morgen. Yami did not cause Morgen's death. Nacht's hostility is best understood through his own guilt, self-loathing, and Yami's resemblance to the reckless person he used to be. Their relationship becomes more cooperative once Nacht confronts that past.
Spoiler scope: this article covers Nacht's backstory, the Spade Kingdom raid, and the manga ending.
Nacht and Yami were friends before the Black Bulls
Chapter 286 is the key chapter for understanding the relationship.
As teenagers, Nacht Faust and Yami Sukehiro got along. Nacht was rebellious, selfish, and eager to do whatever interested him. When he heard about a foreign boy with unusual magic, he sought Yami out. The two became friends and spent time causing trouble together.
Nacht's later contempt can sound as if he always despised Yami, but he did not.
The relationship changed when Yami joined the Grey Deer squad of the Magic Knights. There he met Nacht's twin brother, Morgen Faust. Morgen was compassionate, dutiful, and willing to put himself in danger for other people. He also noticed that Nacht and Yami were similar, a comparison Nacht disliked.
Yami represents a version of Nacht's reckless youth, but their paths diverged. Yami joined the Magic Knights, formed a close partnership with Morgen, and became someone other people could rely on.
Morgen dies stopping Nacht's ritual, not because of Yami
Nacht initiated the ritual that led to Morgen's death. That responsibility is the foundation of his guilt.
House Faust had a hidden history of studying devils. Nacht's Shadow Magic made him suited to the family's forbidden practices, and he embraced that discovery. He successfully formed contracts with four devils and kept pushing further.
Then he attempted to summon Lucifugus, a supreme devil.
Morgen discovered what Nacht was doing and tried to stop him. Nacht ignored the warning and continued the ritual. Lucifugus proved far beyond Nacht's control and killed members of House Faust. Morgen destroyed the relic used in the summoning, forcing Lucifugus back, but suffered fatal damage in the process. He died in Nacht's arms.
Yami did not perform the ritual, summon Lucifugus, or order Morgen into danger. Nacht knows his own choices caused the disaster. That does not mean he intended to kill his brother; it means he cannot forgive himself for the consequences of the ritual he chose to pursue.
Why Yami becomes a target for Nacht's anger
Reading Nacht's hostility as displaced self-hatred helps explain why he directs it toward Yami. This is an interpretation of the flashback and his behavior, not a canon statement that Yami bears responsibility for the ritual.
After Morgen dies, Nacht builds a harsh moral rule for himself. He respects people who are good from the beginning and distrusts people who cause trouble, change later, and then receive praise for improving. That worldview appears in his criticism of the Black Bulls in Chapter 266 and in his judgment of himself during Asta's training.
Yami irritates that worldview. He was Nacht's fellow delinquent and remains crude and reckless, yet he became a captain, recruited outcasts, protected the kingdom, and created a squad whose members risk themselves for one another.
Nacht sees qualities in Yami that resemble his own younger self, but Yami's life also suggests that a flawed person can change. That possibility conflicts with Nacht's refusal to grant himself a second chance.
The Black Bulls reflect the same philosophy: people with bad reputations or painful histories can become better through what they choose to do next.
Does Nacht actually want Yami dead?
His actions do not support that reading.
Nacht leads the plan to invade the Spade Kingdom and rescue Yami and William. He trains Asta because Anti-Magic gives the rescue force a weapon that can challenge devils. That training is also why Asta's strength compared with Nacht's cannot be judged from their first spar alone. When the situation becomes catastrophic, Nacht risks his own life to keep the operation moving.
If his hatred were a literal desire to see Yami die, that rescue effort would make little sense. His hostility and his loyalty coexist.
The outcome of that rescue is covered separately in Yami's fate in Black Clover.
Their relationship changes during the Lucifero fight
Chapter 324 gives Nacht and Yami a major coordinated sequence against Lucifero. They combine their Shadow and Dark Magic through Kids' Playground, using the compatibility of their abilities to pressure a devil who is overwhelming most of the battlefield.
That teamwork does not erase Nacht's personality. He is still sharp, judgmental, and uncomfortable with the Black Bulls' chaotic style. But the story separates his resentment from his actual loyalty.
Chapter 330 pushes that development further. After both men survive near-fatal injuries, Asta welcomes Nacht back to the Black Bulls. Nacht accepts that he belongs with the squad he spent so much time criticizing.
Morgen's return forces Nacht and Yami to face the past together
Morgen returns as a Paladin under Lucius, turning Nacht's deepest guilt into an opponent. Yami is there with Nacht as someone who also shared a bond with Morgen and understands his loss.
In Chapter 385, Yami, Nacht, and Ichika fight Morgen together. Nacht does not confront his past by defeating Yami. He stands beside Yami to face his brother's return as an enemy.
The final chapter, Chapter 392, carries that cooperation into the Black Bulls' future. Yami steps down, and Nacht becomes captain of the squad Yami created. Their actions show trust and mutual respect without requiring Nacht to become soft or sentimental.