Princess Laine ranks among the eight Princesses of Valhalla, potentially the youngest. Her personality mixes cluelessness and brattiness with unexpected kindness, demonstrated when she befriended her past selves during a time-travel mishap. She once held immense admiration for Princess Valkyrie, seeing her as an older sister and competing with Miss Sanada for her attention, a dynamic that later matured into a solid friendship.

She debuted mid-Season 1 when her spaceship crashed on Earth while seeking Valkyrie. Encountering Kazuto and witnessing Valkyrie's child form, she mistakenly blamed Kazuto for corrupting her. Attempting to drive them apart, Laine used her unique transformation ability—mimicking others' appearances nearly perfectly, though her large breasts and antenna remained visible; pulling her antenna reversed the change. Her plans failed when the originals she impersonated appeared, exposing her disguises. Notable transformations included Akina, Princess Hydra, Miss Sanada, Rika Tokino, Spot, and Princess Valkyrie herself. After her schemes unraveled, she accepted Valkyrie's bond with Kazuto and aided the group in infiltrating Valhalla Palace to rescue Valkyrie.

During Season 2, Laine settled on Earth, sharing a home with her academy roommate Princess Chorus. She displayed eccentric habits like excessive snacking, shopping, and drinking—once becoming intoxicated, transforming into Valkyrie, and causing chaotic antics. Her transformation ability went unused this season, with no recorded instances.

Season 3 featured Laine accidentally traveling back in time and interacting with her younger selves. Her past selves observed differences in her personality compared to their future. This encounter solidified her bond with her child self, who later visited the future. She transformed once, taking the form of a Royal Catmaid Squadron member. The episode "Laine, Laine, Laine" centered on this event.

Laine was absent for all of Season 4; Rika speculated she was "probably out in space somewhere, crashing into something." However, her child self from the past appeared in the final episode during the Banquet of the Celestial Comet. While playing with the child Valkyrie, she inadvertently exposed Kazuto and Princess Mehm's wishes, angering Inarba.

Her broader traits include notoriously poor piloting skills, frequently crash-landing spacecraft, and reckless motorcycle driving—though she handled them better than flying saucers. Her transformations often failed due to glamour failures, as her impersonations included out-of-character behavior that alerted others. She maintained a rivalry-turned-friendship with Miss Sanada and lived alongside Chorus on Earth.