Anzu is a central character in the anime, recognized as the younger sister of another key figure, Sumomo. Her background is firmly rooted in her family, where she takes on a self-appointed role as a fierce protector. Despite being the younger sibling, she strives to act as a pillar of strength and often tries to assume a mature, responsible demeanor to shield her loved ones from harm.

At her core, Anzu possesses a powerful and determined personality, marked by an unyielding competitive spirit and a refusal to back down from a challenge. However, this tough exterior masks a more complex inner world. While she desperately wants to be seen as grown-up and dependable, she has a hidden, mischievous side that delights in playful pranks and lighthearted tricks. This contradiction between her mature act and her youthful spirit is a defining trait, as she often struggles with a deep-seated fear of loneliness and a genuine need for companionship and reassurance. Her actions and attempts to appear strong are often driven by this sensitivity and a desire to feel included and loved.

Anzu's primary motivation is the safety and happiness of her family, particularly her older sister, Sumomo. She deeply admires Sumomo but can also feel pangs of jealousy, constantly striving to prove herself worthy and capable. This drive pushes her to take on significant responsibility for her age, acting as a guardian of her household. Within the story’s broader narrative, which involves characters from a high school bowling club who travel back in time to Japan's Sengoku era, Anzu finds herself interacting with this group. Her competitive and strong-willed nature leads to friction with others, such as when she gets into an argument with a character named Nozomi after being confronted about draining a phone battery.

Her key relationships are overwhelmingly defined by her family ties. The bond she shares with Sumomo is the most significant, characterized by a mix of admiration, protectiveness, sibling rivalry, and unconditional support. This connection is the central axis of her emotional world, and her desire to be a reliable figure for her sister shapes most of her decisions. Her development as a character involves navigating the gap between her desire to grow up quickly and the reality of her still-childlike heart. Her journey is about learning to balance her fierce sense of responsibility with the simple joys and playful nature of youth, all while coming to terms with her own vulnerabilities. Notable abilities include her remarkable tenacity and fighting spirit, as she is described as a natural battler who never gives up. Her determination is her greatest strength, seen in moments such as when she is spotted training, hinting at a disciplined and hardworking nature beneath her mischievous surface.