The rise of manga series Demon Slayer: Kimetsu no Yaiba has been meteoric. Hailing from illustrator Koyoharu Gotouge, the original work has earned a place in the pantheon of best-selling manga with 220 million copies in circulation (as of July 2025), and its popularity has been further cemented through the process of translating panels into animation frames.
The results speak for themselves – not only is the anime series largely considered one of the best anime of the 2010s, but its first feature-length film, Infinity Train, took the Japanese and global box office by storm, shattering one milestone after another. In a similar fashion, Demon Slayer: Kimetsu no Yaiba – Infinity Castle, the fourth movie from the franchise, has made a similar, if not larger, splash, driven by the staple elements that have shaped the franchise’s appeal, including visually decadent animation, exhilarating action, and strong characterisation.
The character-focused storytelling, in particular, will take centre stage here. Serving as the direct sequel to the anime’s fourth season, the first in a planned trilogy set to adapt the manga’s Infinity Castle arc follows protagonist Tanjiro Kamado (voiced by Natsuki Hanae) and his fellow demon slayers as they battle the Upper Moons, the most powerful of Muzan Kibutsuji’s (Toshihiko Seki) subordinates in the titular multidimensional stronghold.
While navigating the shifting space, the group is forcefully separated, mostly into pairs, in a high-stakes showdown against various powerful foes. It sets the perfect stage to delve deeper into the dynamics of each duo, starting with Water Hashira Giyu Tomioka, voiced by Takahiro Sakurai, the industry veteran behind some of the most popular voices in video games and anime – including Final Fantasy VII’s Cloud Strife, Jujutsu Kaisen’s Suguru Geto, and Code Geass’ Suzaku Kururugi – and Tanjiro himself.
Handling a key moment comes with certain expectations, and the former recognises the importance of doing it justice. In an interview with select Singapore-based media that Geek Culture attended, the 51-year-old highlights how he sought to replicate his character’s relationship with Tanjiro from the manga.
“The key point for me was the relationship between Tanjiro and Giyu. I wanted to keep the consistency between the anime and manga versions of their relationship,” shares Sakurai.
More than just a highly anticipated outing, it represents the growth of both characters since their first encounter. The demon-slaying pair initially started on a hostile, albeit one-sided, note, but have come to develop mutual respect and care for each other, following their tag-team battle against Lower Rank Five demon Rui during the Mount Natagumo Arc. From there, the simmering hints of camaraderie have carried over to subsequent arcs, extending to the recent Hashira Training Arc, also the subtitle for Season 4, and now, The Infinity Castle Arc.
As the voice actor succinctly puts across in a public address before a premiere screening, held in conjunction with a red carpet event at Shaw Lido Singapore, “[Giyu’s] transition reflects how encounters can make a huge impact on humans and the relationships they hold.”
The development of interpersonal relationships wouldn’t be quite possible without undergoing some intrapersonal changes, however. Sporting a calm, stoic demeanour, the Water Hashira evokes the imagery of cool, which has endeared him to many and serves as a major contributing factor to his massive popularity (Giyu ranked fourth and second place in both official popularity polls).
It wasn’t until the Hashira Training Arc that the reason behind his taciturn character surfaced, revealing a part of him hidden not by choice, but circumstance. For Sakurai, a specific conversation in the fourth anime season pointed to the first signs of Giyu’s complexity – the scene with Insect Hashira Shinobu Kocho, where she goes, “You’ll be disliked by other people,” only for the former to respond, “No, that’s not true”.
“If this came from a calm, emotionless person, the person would normally reply, ‘Well, I don’t care if people don’t like me,” he explains. “Instead, [Giyuu] said, ‘No, that’s not true,’ which was already the hint of him not being just a take-it-or-leave-it kind of personality.”
Talk about an astute observation.
As Demon Slayer: Kimetsu no Yaiba – Infinity Castle makes its way across the globe, fans can expect to catch the fan-favourite character back in action. The swordsman has come a long way – and in more ways than one, as Sakurai wasn’t aware of the original work before joining the cast. Now, though? Demon Slayer is a household name.
Amid a lighthearted anecdote of how the cast members would have a preferred seat in the recording studio, with most, if not all, choosing the corners, the voice actor reveals that the first encounter between Giyu and Tanjiro holds “the most special place in his heart” when recounting his character debut scene.
“In the beginning, Giyu saved Tanjiro, then in the latest episode, he’s saved by Tanjiro. At the end of the day, I feel like it’s fate that the two of them met,” surmises Sakurai on their dynamics, separately, in the theatre hall before the start of the premiere screening.
Demon Slayer: Kimetsu no Yaiba – Infinity Castle is playing in theatres.
Si Jia is a casual geek at heart – or as casual as someone with Sephiroth’s theme on her Spotify playlist can get. A fan of movies, games, and Japanese culture, Si Jia’s greatest weakness is the Steam Summer Sale. Or any Steam sale, really.
