Rei Hitoma, a self-professed recluse due to past wounds, embarks on a teaching job in the serene mountains, only to discover that the school caters to demi-humans aspiring to attain full humanity. With a motley crew including a mermaid, a werewolf, a rabbit, and a bird under his wing, Rei's task is to impart human knowledge while possibly unraveling his own inner truths. This tale unfolds in a unique school setting, devoid of alternate realities or reincarnations, focusing on a teacher and his extraordinary pupils' quest for humanity.