Aizawa Ayumu reluctantly returns to his childhood town of Tana to stay with his father, enticed by a promise of a mountain bike from his mother. Haunted by enigmatic memories of his past there, Ayumu encounters Miku, a secretive girl, strange glowing phenomena, and eerie reflections in animals' eyes. Amidst a quaint backdrop, a curious female narrator, an enigmatic forest, and the mysterious Wakkun in familiar attire, Zettai Shonen weaves a tale of unresolved secrets within the tranquility of everyday existence.