"Sasurai-kun" is a 1983 anime series adapted from the manga by Kazuo Koike and Ryoichi Ikegami. The story centers around Tatsuya, a young man with a mysterious past and a unique ability to sense danger, which he uses to navigate a world filled with crime, corruption, and moral ambiguity. Tatsuya, often referred to as "Sasurai-kun" (Wandering Boy), drifts from place to place, encountering various individuals and situations that challenge his sense of justice and survival instincts.

The narrative unfolds as Tatsuya becomes entangled in the lives of those he meets, often stepping in to protect the vulnerable or confront those who exploit others. His journey takes him through urban landscapes and rural settings, where he faces yakuza, corrupt officials, and other antagonists. Despite his rough exterior and pragmatic approach, Tatsuya possesses a strong moral compass, often aiding those in need while avoiding unnecessary violence. His ability to foresee danger, combined with his combat skills, makes him a formidable yet reluctant hero.

Throughout the series, Tatsuya's past is gradually revealed, shedding light on the origins of his abilities and the events that shaped his solitary lifestyle. Flashbacks and encounters with figures from his past add depth to his character and provide context for his actions. The series explores themes of redemption, justice, and the struggle to maintain one's humanity in a harsh and unforgiving world.

Supporting characters include a range of individuals Tatsuya assists or confronts, from innocent bystanders caught in dangerous situations to hardened criminals with their own codes of honor. These interactions highlight the complexities of human nature and the blurred lines between right and wrong. The episodic structure of the series allows for self-contained stories while maintaining an overarching narrative that ties Tatsuya's journey together.

"Sasurai-kun" is notable for its gritty tone, realistic portrayal of societal issues, and focus on character-driven storytelling. The series balances action and drama, with Tatsuya's internal conflicts and external challenges driving the plot forward. The anime remains a compelling exploration of a lone wanderer's quest for purpose in a world rife with moral ambiguity.