Ikuko Wakatsuki is a high school student and the owner of Mametarou, a mixed-breed dog. She lives with Mametarou, who expresses deep affection for her, forming the central human relationship in his life. Mametarou strongly dislikes her friend Akiyoshi, creating a recurring point of tension within her social circle from the dog's perspective.

Her daily life involves typical high school activities. Mametarou frequently escapes whenever she leaves for school, a pattern tying his daily adventures directly to her structured schedule. Later official media depicts her experiencing romantic feelings, described as a "lovesick" storyline. While specific romantic interests remain unspecified, this development introduces emotional challenges that intertwine with her bond to Mametarou and her connections with others.

Her interactions are grounded in ordinary human experiences. Unaware of the story's narration, she does not perceive Mametarou's viewpoint, including his thoughts and conversations with other dogs that humans cannot hear.