Shige Kitabatake is a high school student defined by crippling timidity and social anxiety. Orphaned young and raised by his grandmother, this upbringing fostered his reserved nature. He suffers persistent bullying, especially from Naoto Tachibana, resulting in profound low self-esteem and a habit of avoiding confrontation.

Shige's life shifts dramatically upon encountering the injured dragon Ryūjin. Ryūjin grants Shige a portion of his power, enabling transformation into a dragon-human hybrid. This ability drastically enhances Shige's physical capabilities and slowly builds his confidence. Initially, Shige wrestles with controlling this power, fearing its consequences; stress often triggers unintentional transformations.

Shige holds deep, unspoken feelings for his childhood friend, Akari Kirishima. His prior lack of confidence prevented him from confessing. Protecting Akari becomes a central motivation, driving him to embrace his dragon powers and confront enemies.

As threats emerge from other dragon-powered individuals and organizations coveting Ryūjin's power, Shige faces escalating conflicts. Necessity forces him to significantly improve his control over transformations and hone associated abilities like enhanced strength, speed, flight, and dragon breath, refining his fighting skills.

Shige's journey demands he confront his fears and insecurities directly. The responsibility of protecting loved ones and the world from growing dangers compels him to mature. He gradually develops greater assertiveness and courage, evolving from a passive victim into an active protector. While retaining his fundamentally kind and gentle core, he becomes more willing to stand up for himself and others.

His bond with Ryūjin deepens, revealing more about the dragon's history and the nature of the bestowed power. Shige learns Ryūjin sought him out, sensing a compatible spirit. This connection becomes symbiotic, with Shige's growth and actions influencing Ryūjin's recovery and state.

Shige forms alliances with others possessing unique abilities, learning to trust and rely on companions beyond Akari. He grapples with complex moral dilemmas involving power, sacrifice, and the consequences of his actions. His development culminates in fully accepting his dual human-dragon nature, integrating the power instead of fearing it, to confront ultimate threats to peace.