"Stars Align" centers around the lives of middle school students who join their school's soft tennis club, a sport similar to tennis but played with softer balls and paddles. The story primarily follows Toma Shinjou, a skilled but reserved player, and Maki Katsuragi, a transfer student with a troubled home life. Maki is initially reluctant to join the club but agrees after Toma offers to pay him for his participation. As the series progresses, the dynamics within the team and their personal struggles come to the forefront.

The narrative delves into the personal challenges faced by each team member, exploring themes such as family dysfunction, identity, and societal expectations. Maki's difficult relationship with his abusive mother and absent father is a recurring focus, highlighting his resilience and emotional struggles. Toma, on the other hand, grapples with the pressure of living up to his family's expectations while trying to maintain his individuality. Other characters, such as Rintaro Futsu, Yuu Asuka, and Shingo Takenouchi, also face their own issues, ranging from parental neglect to gender identity and self-acceptance.

The soft tennis matches serve as a backdrop for the characters' growth, both individually and as a team. The series balances the competitive aspects of the sport with the emotional and psychological development of the players. As the team prepares for tournaments, their bonds strengthen, and they begin to confront their personal demons. The narrative does not shy away from depicting the harsh realities of adolescence, including bullying, mental health struggles, and the impact of societal norms.

"Stars Align" is notable for its realistic portrayal of teenage life and its willingness to address complex and often overlooked issues. The characters' journeys are intertwined with their experiences on and off the court, creating a narrative that is both compelling and thought-provoking. The series concludes with an open-ended finale, leaving room for interpretation while emphasizing the ongoing nature of the characters' growth and challenges.