"March Comes in Like a Lion" centers on Rei Kiriyama, a 17-year-old professional shogi player who lives alone in Tokyo. Rei is a prodigy in the world of shogi, having turned professional at a young age, but his success comes with emotional and psychological burdens. Orphaned at a young age, Rei was taken in by a shogi-playing family, but their cold and competitive environment left him feeling isolated and disconnected. Struggling with depression and loneliness, Rei’s life begins to change when he meets the Kawamoto sisters—Akari, Hinata, and Momo—who offer him warmth, kindness, and a sense of belonging.

The narrative alternates between Rei’s professional shogi career and his personal growth. As a professional player, Rei faces intense pressure, rivalries, and self-doubt, particularly in matches against seasoned opponents like the enigmatic and intimidating Harunobu Nikaidou. The series delves into the intricacies of shogi, portraying it not just as a game but as a reflection of the players’ emotions, strategies, and personal struggles. Rei’s matches often serve as metaphors for his internal battles, highlighting themes of perseverance, self-discovery, and resilience.

The Kawamoto sisters play a pivotal role in Rei’s life. Akari, the eldest, is nurturing and compassionate, often acting as a maternal figure. Hinata, the middle sister, is empathetic and perceptive, forming a deep bond with Rei as they share their vulnerabilities. Momo, the youngest, brings joy and innocence to Rei’s life, helping him reconnect with his own childhood. Through his interactions with the sisters, Rei gradually learns to open up, confront his past, and find meaning beyond shogi.

The series also explores the lives of other shogi players, such as Rei’s mentor, Kōhei Takanashi, and his rival, Nikaidou, who suffers from a chronic illness but remains fiercely determined. These characters add depth to the narrative, showcasing the diverse motivations and challenges within the shogi community. Themes of family, friendship, and healing are interwoven throughout the story, as Rei navigates his relationships and strives to overcome his inner turmoil.

"March Comes in Like a Lion" balances its emotional depth with moments of humor and levity, creating a nuanced portrayal of Rei’s journey. The series is a poignant exploration of human connection, personal growth, and the pursuit of purpose, set against the backdrop of the competitive and introspective world of shogi.