Ayame Shaga is a main character in the Ben-To series, known by the title Beauty by the Lake, a moniker she earned after eating a bento on a bench in a park next to a lake and falling asleep there. She is the half-Italian first cousin of the protagonist, You Satou, and was born on the same day and in the same hospital as him. A first-year high school student, she serves as the president of the Gaming Club at Sawagi High School.

In terms of personality, Ayame is a vivacious and highly spontaneous individual who is not shy about expressing her affection. She is particularly playful and flirtatious with her cousin Satou, often leaning against him or pressing her chest against his back or arm in a way that leaves him flustered. This behavior extends to others, as she is also fond of playfully fondling her female classmate Hana Oshiroi. Beneath this confident and teasing exterior, Ayame can be stubborn and is easily irritated by insults. She also displays a significant competitive streak, especially in her rivalry with the powerful fighter known as the Ice Witch, Sen Yarizui, and becomes excited at the prospect of fighting her. This rivalry is fueled by jealousy when Satou prefers to spend time with Sen instead of her, though she remains protective of him. Despite her bold demeanor, she has a vulnerable side and can become flustered and intimidated by more dominant individuals, such as the student body president Ume Shiraume.

Ayame’s primary motivation within the story is to challenge and defeat Sen Yarizui in the half-priced bento brawls. For her, the battle is not just about obtaining the meal but an excuse to fight a worthy opponent and prove her own strength as a top-tier wolf. Her role is that of a formidable brawler from the western district who invades the territory of the Ice Witch to stake her claim. She acts as a significant rival to Sen and a love interest for Satou, creating a romantic tension that is more overt than with other female characters. Her key relationships include her cousin Satou, who she often tries to manipulate through her wiles; her friendly rival Sen Yarizui; her playful target Hana Oshiroi; and the object of her fear, Ume Shiraume, who has a romantic interest in her.

Throughout her introduction, Ayame is presented as a supremely confident and powerful wolf, but she undergoes development as this image is systematically dismantled. She is quickly overpowered by Sen in a direct fight and is easily dominated by Ume, revealing that for all her talk and bravado, she is not invincible and has moments of insecurity. These defeats serve to humble her and show that she is a "paper tiger" in some respects, though her fighting spirit remains strong.

Regarding her abilities, Ayame is a highly skilled bento brawler who fights with considerable speed and quick reflexes. Her signature technique involves using disposable chopsticks as weapons, allowing for creative and dynamic attacks reminiscent of martial arts films. While a formidable fighter, she is not on the level of the strongest wolves, as she falls short against Sen Yarizui. Outside of combat, Ayame is an expert in Sega video games, particularly the Virtua Fighter series, and is nearly impossible to beat; she has defeated Satou hundreds of times, with him only achieving a fraction of the wins.