Laila Seiren is a fourteen-year-old girl from the anime Hero Tales. She is the adopted younger sister of the protagonist, Taito, and the daughter of Souei, the leader of Seiryutou. Laila is a spirited and headstrong young woman who frequently quarrels with Taito. She never loses these arguments, a dynamic that hints at her sharp tongue and stubborn nature. Beneath this bickering exterior, however, she genuinely cares for Taito and is deeply protective of him. She is the only person capable of stopping Taito when he becomes reckless or when he loses control of his immense power, acting as his emotional anchor. Her ability to remain calm and authoritative in those moments is her most defining trait, as she can physically or verbally intervene to pull him back from his berserk state.

Laila is motivated by her loyalty to her family, especially Taito, and her desire to protect those she loves. She does not possess supernatural abilities like the Hokushin-Tenkun (the celestial stars), but her strength lies in her unwavering presence. In the story, she accompanies Taito and his ally Ryuukou on their journey to reclaim the legendary sword Kenkaranpu and confront the forces threatening their land. Her role is largely supportive; she offers guidance, logistical help (such as enlisting the ship captain Koyou to rescue Taito and Ryuukou during a flood), and moral support. The relationship between Laila and Taito undergoes subtle change as the series progresses; she begins to see him not just as a brother she looks after, but as a man growing into his own destiny. Their bond remains central to his character development. Notable abilities beyond her influence on Taito are not detailed; she relies on her wit, determination, and close connection to those around her to contribute to the group.