Love is what we cling to, but holding on too tightly can stifle personal growth or smother the other person. For Natsumi, she clung to her little sister Haru. It's easy to understand why when looking at their family dynamic. Their parents were the product of an arranged marriage that never clicked and due to some old-fashioned family values, their boisterous mother was constantly at odds with their more traditional father. Natsumi sees herself as a reflection of her mother; she's goofy, the way to her heart is through her stomach, and her goals for her life are modest. As a growing teen she aches for her father's approval until his affair and remarriage brings a new woman into the household. A woman who has more in common with her diminutive, feminine sister. Her mother leaves her and Natsumi quits vying for her father's approval, instead finding comfort in an intense closeness with Haru.

Co-dependency is an underlying theme in Haru's Curse, at least as much as guilt, individuality, and grief. The skillful emotional drama unfolds with each chapter named after a particular month, but it'd be closer to say that the story travels through the seasons of three people's lives. This metaphor is not subtle: Natsumi and Haru's names are homonyms for Summer and Spring, respectfully, and when Natsumi discovers Haru's blog she finds her sister writing about her experience with cancer treatment under the alias "Aki" for Autumn. The sisters' personalities are reflective of their namesake, with Haru being "flower-like" in her demeanor, invoking the idea of a shrinking violet, whereas Natsumi is brash, forward, and athletic. While those character types are far from unique, it's the honesty of the women's relationship dynamic that contributes to the story's realism. Natsumi appears to be a "what you see is what you get" type, but it's her own insecurity that feeds her altruistic actions. She learned early that she was not good enough for the adults in her life and is initially hostile to Togo when he begins courting Haru. When Haru gets sick, she reroutes her entire life in order to become her potential caretaker, going as far as majoring in nutrition. This is in part because she loves her sister of course, but it's also because she still believes they'll live together despite Togo being lined up as her future brother-in-law.

The futility of her actions barely occurs to her, but Natsumi knows the extent of her devotion to Haru is unhealthy. She's distraught by what she thinks are romantic feelings for her sister. However, Haru's Curse is chaste in its depictions of romance. While Natsumi's feelings for Haru are no doubt intense, they strike me as co-dependent much more than something truly romantic. However, the space between her feelings for Haru and her feelings for Togo is small, likely intentionally. Her initial agreement to date Togo has nothing to do with protentional feelings for him. It's an agreement made out of grief and Natsumi's futile attempt to "compromise" Haru's death. She hopes that by dating him under specific circumstances, only going to places he had previously taken Haru, she'll recapture a closeness with her sister. Of course, that's not what Togo had in mind at all, but he accepts her stipulations.

What Haru's Curse does exceptionally well is impart the reader to the internal lives of its cast. The initial chapters are told from Natsumi's perspective but later shift to Togo and eventually Haru to give a better understanding of their feelings and internal motivations. Togo is far from the aloof business heir that he is initially presented as and instead more akin to a bird in a gilded cage. He's lived a life where everything was provided for him easily so long as he jumped when he was told. Natsumi's vivacity strikes a chord in Togo that causes him to question his own satisfaction in the way that he's lives. Meanwhile, both parties seem to have overestimated Haru's naivete and gentleness. Her death looms over the entire story as Natsumi and Togo try to discover which decisions they can live with and what pain is tolerable.

For readers sensitive to such content, there is a two-chapter discussion of suicide within the book and the handling of the topic is dicey. The series falls back on the threat of "if you die, then I'll die" to navigate the crisis so that one character abstains out of concern or potential guilt for the other. However, it's not central to the story thematically and the feelings at the time seem appropriate. I would say that all the characters' actions feel purposeful. Haru's Curse isn't playing up feelings for cheap drama here.

By the volume's end (Vertical has combined the two tankobon into a single volume release) it felt like both characters had truly grown into more mature and confident versions of themselves. There's an overarching message that grief is eternal. It's a feeling that always sits within you. But you cannot disappoint or make the deceased sad; you have to make your choices for yourself.