Kasen Kanesada is an uchigatana sword warrior from the anime Touken Ranbu Kai Kyoden. He was forged by the second generation of the Kanesada school, commonly known as Nosada, who is considered the greatest among the successive generations of that swordsmith lineage. The name Kasen is derived from the Thirty-Six Immortals of Poetry, a group of classical Japanese poets, which he points to as evidence of his own elegance. However, the origin of the name carries a darker undertone, as it also refers to the thirty-six men who were killed by one of his former masters.

Kasen self-identifies as a literary or cultured sword, a "sword of the arts," and he takes great pride in this identity. He is deeply devoted to the concept of "furyu," or elegance, and seeks to find or impart this quality in all aspects of life, from the changing of the seasons to the equipment used in battle. He claims expertise in refined pursuits such as Japanese poetry, the tea ceremony, and connoisseurship of art and artifacts. His speech and mannerisms are generally polite and composed, befitting his cultivated persona.

This cultured exterior, however, masks a ruthless and merciless side that emerges during combat. His dialogue on the battlefield is starkly violent, calling for opponents to present their necks and declaring that those who do not understand elegance deserve to perish. This duality is a direct inheritance from his most famous historical wielder, a daimyo known for both his patronage of the arts and his brutality. Kasen acknowledges this tension himself, noting that without strength, he could not persist as a man of the arts in a harsh world. He has a muscular build, which contrasts with his intellectual self-image, and he occasionally falls into the habit of relying on physical force. Despite his professed love for the arts, he admits to disliking calculations.

Kasen's primary motivation is to uphold his standard of elegance in all things, whether in the peaceful daily life of the citadel or on the battlefield. He serves as a sword warrior to protect history from the Retrograde Army, but he approaches this duty through his unique aesthetic lens. His role in the story is often that of a composed, if eccentric, team member whose artistic perspective can sometimes alienate him from others. He strives to appreciate beauty even amidst conflict and wishes to be grouped with others who share his understanding of grace.

His key relationships are often influenced by shared history or differing philosophies. He shares a connection with other swords formerly owned by the Hosokawa family, such as Sayo Samonji, whom he affectionately calls "Oh-Sayo". He also has a relationship with Izumi no Kami Kanesada, a sword by a related smith, whom he refers to as "Nosada," acknowledging their shared lineage. While he is dedicated to elegance, he can become self-conscious when his artistic expressions are not understood by his comrades, revealing a vulnerable side beneath his confident demeanor.

Throughout his development, Kasen grapples with the contrast between his violent nature as a weapon and his aspiration to be a cultured individual. While he remains committed to his artistic passions, he also accepts the reality of his existence as a sword, acknowledging that the true path of a blade is to fight until its end. His journey involves not only perfecting his craft in poetry and tea but also reconciling his lethal purpose with his love for beauty.

As a warrior, Kasen wields his own blade in close-quarters combat, with a short attack range. He is a well-balanced fighter with solid stats in both offense and defense. His abilities are not just physical; his keen eye as a connoisseur allows him to appraise swords, armor, tea utensils, and even food ingredients with great skill. In his downtime, he is also skilled at cooking and crafting armor.