"Le Portrait de Petite Cossette" is a three-volume manga series written and illustrated by Asuka Katsura, based on the original anime OVA series of the same name. The story revolves around Eiri Kurahashi, a young art student working part-time at his uncle’s antique shop. While cleaning the shop, Eiri discovers a Venetian glass goblet that seems to hold a mysterious presence. Upon gazing into it, he becomes entranced by the image of a young girl named Cossette d’Auvergne, who lived centuries ago. Cossette reveals herself to Eiri as a spirit trapped within the goblet, bound by a tragic curse.

Cossette explains that she was murdered by her lover, Marcello Orlando, an artist who painted her portrait and became obsessed with her. Marcello’s jealousy and madness led him to kill Cossette, and her soul became trapped in the goblet as a result of his dark magic. To free her, Eiri must take on Marcello’s sins and endure the suffering inflicted by the curse. Eiri, increasingly captivated by Cossette, agrees to bear the burden, despite the physical and psychological toll it takes on him.

As Eiri delves deeper into the curse, he experiences hallucinations, physical pain, and encounters with malevolent spirits tied to Cossette’s past. His relationships with those around him, including his childhood friend Shouko, become strained as he becomes more isolated and consumed by his obsession with Cossette. Shouko, concerned for Eiri’s well-being, tries to intervene, but Eiri’s fixation on freeing Cossette blinds him to the dangers he faces.

The narrative explores themes of love, obsession, and sacrifice, as Eiri struggles to reconcile his feelings for Cossette with the reality of her tragic existence. The curse’s demands grow increasingly severe, pushing Eiri to the brink of madness. Ultimately, the story builds toward a climactic confrontation with the lingering remnants of Marcello’s malevolence, as Eiri seeks to break the curse and grant Cossette peace.

The manga’s gothic atmosphere and psychological intensity are central to its storytelling, blending supernatural horror with a haunting romance. The characters are defined by their emotional struggles, with Eiri’s descent into obsession and Cossette’s tragic history serving as the core of the narrative. The series maintains a dark, ethereal tone throughout, emphasizing the interplay between beauty and tragedy in its exploration of love and redemption.