Sai Nanohana, father to Jiyu Nanohana, is a ghostwriter for historical samurai novels haunted by the death of his wife, who succumbed to illness alone while he worked in his office. Driven by guilt, he abandons his office to work from home, clinging to his daughter with an overprotectiveness that often casts him as a comedic, misunderstood stalker, sparking chaotic confrontations. Though he pens gripping tales under pseudonyms, he secretly chafes against anonymity, yearning to claim his stories.

Beneath his bumbling exterior lies hidden skill: he trained Jiyu in the Yagyuu Shinkageryuu Mutodori, a defensive swordsmanship art, foreshadowing his deeper resolve. When Jiyu inherits the mantle of Yagyu Jubei’s successor, his paternal instincts shift from comedic interference to strategic support. In a pivotal act of sacrifice, he surrenders his body to an antagonist’s possession, challenging Jiyu to hone her strength and vanquish the threat.

Years later, at Jiyu’s urging, he ventures into romance fiction under his own name, only to falter when lured back to ghostwriting by old professional ties. His past resurfaces with Mikage, a married former colleague, rekindling unresolved affections that fracture his fragile balance. Manipulated by Freesia Yagyu into slapping Jiyu during a heated confrontation, he confronts his flaws, mending their bond through unwavering support in her battles.

Ultimately, he navigates parenthood and prose under Mikage’s mentorship, his journey tracing a path from guilt-stricken jester to a grounded figure weathering loss, creative strife, and the scars of absence—steadfast as Jiyu’s anchor.