Kan Kikuchi is an intimate friend and former classmate of Akutagawa Ryuunosuke. Their relationship is comfortable and informal, marked by the nicknames "Ryuu" for Ryuunosuke and "Kan" for Kikuchi. Akutagawa feels completely at ease with Kikuchi, seeing in him an older brother figure; they exchange sass and light-hearted remarks without reservation.

Their friendship began at First Higher School and continued when both enrolled at Tokyo Imperial University. There, alongside fellow former classmate Kume Masao and others, they collaborated to publish the literary coterie magazine "Shinshichou," reflecting their shared intellectual and creative pursuits during their university years.