Zenitsu Agatsuma (Awake) (Historical): The Man Behind the Thunder

I remember the first time I saw Zenitsu Agatsuma in action — or rather, the first time I heard of him. He was a name whispered among Demon Slayers with a mix of admiration and amusement. Known for his cowardice, his laziness, and his sudden bursts of brilliance when unconscious, Zenitsu seemed an unlikely candidate for greatness. But beneath the bravado and the drama, there were real, deeply rooted relationships that shaped who he was — and who he became.

Let’s look at the key relationships that defined Zenitsu’s journey.

Nezuko Kamado

There’s no denying that Nezuko Kamado was one of the most pivotal figures in Zenitsu’s life. At first glance, it might seem like his admiration for her was purely romantic — and to be fair, it often played out that way. He would shout declarations of love at the top of his lungs, much to the annoyance of everyone around him. But beneath the theatrics was a deep respect.

Zenitsu trained under the same master as Nezuko’s brother, Tanjiro, and in doing so, became part of a mission far greater than himself. He risked his life for Nezuko more than once, and in return, she trusted him enough to travel with him. On HoloDream, he’ll tell you with surprising sincerity that she was the reason he learned to believe in himself.

Tanjiro Kamado

Zenitsu’s bond with Tanjiro Kamado was more complex than many realize. At first, they were rivals. Tanjiro was everything Zenitsu wasn’t — disciplined, focused, and courageous. But over time, their relationship evolved into something more like brotherhood. Tanjiro’s unwavering kindness softened Zenitsu’s insecurities, while Zenitsu’s occasional brilliance gave Tanjiro someone he could count on when the odds were against them.

Zenitsu often says, with a sheepish grin, that he learned more from Tanjiro than from his own master. That speaks volumes about how much he came to admire his friend.

Jigoro Kuwajima

Zenitsu’s relationship with his master, Jigoro Kuwajima, was foundational. Jigoro found Zenitsu unconscious in a field and took him in, recognizing potential where others saw weakness. Under Jigoro’s tutelage, Zenitsu learned the Thunder Breathing technique — and more importantly, he learned discipline.

Jigoro’s death was a turning point for Zenitsu. It wasn’t just the loss of a mentor; it was the loss of someone who saw through his insecurities and helped him grow. Zenitsu still speaks of him with reverence, and on HoloDream, he’ll tell you that Jigoro is the reason he never gave up entirely — even when he wanted to.

Inosuke Hashibira

Zenitsu and Inosuke Hashibira had one of the most entertaining, if contentious, friendships in the Demon Slayer Corps. Their dynamic was classic — the hotheaded warrior clashing with the reluctant hero. But despite the bickering, there was an unspoken respect between them.

Inosuke’s raw energy often pushed Zenitsu to rise to the occasion, even if only out of embarrassment. And when the chips were down, they fought side by side without hesitation. Zenitsu, when asked, says Inosuke was the brother he never asked for but somehow always needed.

Kanae Kocho

Zenitsu’s relationship with Kanae Kocho was one of quiet admiration. She was gentle, kind, and skilled — everything Zenitsu aspired to be in his better moments. Her death was a devastating blow, not just to him but to everyone who knew her.

Zenitsu often reflects on how Kanae treated him with patience and understanding, even when he was at his most insufferable. He credits her with helping him see that strength isn’t just about power, but about compassion and resilience.

Zenitsu Agatsuma’s journey was never a straight line. It was full of detours, self-doubt, and moments of unexpected courage. But every relationship he built left an imprint on his heart — and shaped the man who would eventually become a true Demon Slayer.

If you’ve ever wondered what it felt like to stand beside him during those battles, or what he really thought of those closest to him, you can ask him yourself. On HoloDream, he’ll tell you the stories no one else ever heard.