Lala Gonzales is a transfer student from Mexico who arrives at Yagami High School during the second semester. She was raised primarily by her father, a former luchador who turned to heavy drinking after her mother abandoned the family when Lala was very young. Her father taught her the art of Lucha Libre, and she became a highly skilled practitioner of this wrestling style. She originally came to Japan with her father, who had dreamed of emigrating there to find their fortune; Lala accomplished that dream on her own.

In personality, Lala is hot-tempered, easily provoked, and quick to resort to physical confrontation. She has a perpetually sour expression and a violent temper that makes others wary of approaching her. She is described as the direct opposite of Karen Ichijou, being tall and well-endowed while Karen is shorter and more petite. Lala can be antagonistic and aggressive, but she is also driven by a deep-seated emotional wound: her mother, who left her, was named Karen. Learning that the girl she saw as a rival also bore that name fueled her initial hostility and motivated her transfer to Yagami High, as she wanted to settle a personal score.

Lala's primary motivation is rooted in this emotional conflict. Her rivalry with Karen Ichijou is central to her role in the story. She joins the same amateur wrestling club as Karen and frequently shouts her name when they meet. However, beneath the surface of her animosity, she is genuinely impressed by Karen's strength. Over time, her antagonism softens, and the two eventually become good friends. Lala is also pursued by Kyousuke Imadori, who is attracted to her bust size. She despises him for his lecherous behavior, especially after he once managed to grope her, and she beats him senseless whenever he provokes her sufficiently.

Key relationships include her rivalry-turned-friendship with Karen Ichijou, her antagonistic dynamic with Kyousuke Imadori, and her friendships with Harry Mackenzie and Masakazu Tougou, who both look out for her. She works alongside Karen at a fast food restaurant, where her intimidating demeanor discourages customers from approaching her counter; she has been known to grab annoying customers and drag them inside for a beating.

Lala's development across the second semester involves a gradual softening of her hostility toward Karen, evolving from a bitter rival into a genuine friend. Her character does not undergo a radical transformation but shows growth in her ability to let go of the resentment tied to her mother's abandonment and in forming bonds with people around her.

Her notable ability is her mastery of Lucha Libre, which makes her a formidable fighter. She is also revealed to be a good singer, with her singing featured in episodes of School Rumble - Second Term.