Abe no Yasuna is a young samurai imprisoned under unclear circumstances. The vixen Rizu, disguised as the human woman Kuzunoha, frees him to halt the fox hunter Akuemon. Upon liberation, Yasuna pledges to aid Rizu in protecting foxes but insists on returning to his home province before fulfilling this vow.

His background intertwines with the Shinoda Forest legend, where his ancestor Abe no Yasuna rescued a white fox from hunters. That fox transformed into a woman also named Kuzunoha, married the historical Yasuna, and bore their son Abe no Seimei. While the anime omits direct depiction of these ancestral events, they contextualize Yasuna's story.

Yasuna later returns to discover Akuemon has abandoned fox hunting under Rizu's influence, eliminating the threat to foxes. With the conflict resolved, Yasuna shifts his purpose: he formally adopts Akuemon and Rizu's infant son, who grows to become the legendary onmyōji Abe no Seimei, inheriting supernatural gifts from his fox spirit mother.

After Rizu departs to rejoin her fox kin, Yasuna raises Seimei alone. The narrative implies this upbringing occurs at Abeno, the historical region of the Abe clan. Yasuna's activities following Seimei's adoption remain undetailed.