Marta Nolan is the protagonist of the anime Shin Aim for the Ace!, a young high school student who enrolls at Nishi High School, a school renowned for its elite tennis program. She begins playing tennis after becoming captivated by the graceful playing style of the older star player Reika Ryuzaki, known as Madame Butterfly. Marta is a complete beginner at first, but she possesses natural aptitude and, more importantly, an unyielding willpower that drives her to improve. Her personality is marked by initial shyness and self-doubt, as she often struggles with anxiety and a lack of confidence in her abilities on the court. However, beneath that insecurity lies a deep determination and a passionate love for tennis. Her primary motivation is to become a great tennis player, inspired by her admiration for Madame Butterfly and later by the rigorous training methods of the new coach, Jin Munakata. Coach Munakata recognizes Marta's hidden potential and singles her out for intense, often harsh lessons, pushing her beyond her limits. This puts her at odds with some of her upperclassmen, who resent her sudden promotion, but it also forces her to grow mentally and physically. Marta’s role in the story is that of the underdog protagonist whose journey from a clumsy novice to a competitive tournament player forms the central narrative. She develops key relationships with her best friend and teammate Maki Aikawa, who supports her throughout, and with Takayuki Todou, a talented male tennis player who becomes her romantic interest. Her development is defined by her gradual overcoming of mental weakness. Under Coach Munakata’s guidance and through her own perseverance, she learns to channel her nerves into focus and becomes a representative for her school in important junior matches. Her notable abilities include her strong athletic instincts, a fierce determination that allows her to endure grueling training, and a growing tactical sense on the tennis court. As the series progresses, she transforms from an insecure beginner into a mentally tougher and more skilled player, embodying the theme of striving for excellence despite personal struggles.