Keiko Ayano enters the virtual reality game Sword Art Online under the alias Silica, a name blending silicon dioxide’s chemical abbreviation (SiO) with her real name’s elemental tie and a desire for a playful moniker. Her signature red ribbons, evoking oxygen atoms bonded to silicon, visually echo this scientific inspiration. As a dagger-wielding combatant, Silica earns the title "Beast Tamer" by forging an unbreakable bond with Pina, a dragon-like familiar. This connection defines her journey, marked by grief when Pina perishes temporarily and unwavering resolve to restore her companion. The bond transcends the digital realm, manifesting later in her adoption of a real-world cat bearing the same name. Her blend of kindness and inexperience leads to a perilous misadventure in the Forest of Wandering, where overconfidence strands her without Pina. The ordeal cultivates humility and deepens her appreciation for partnership. Socially reserved, she flusters easily in romantic contexts or physical interactions—exemplified by her discomfort when Kirito touches her Cait Sith avatar’s tail, sparking a "super weird feeling." Transitioning to Alfheim Online as a Cait Sith, Silica retains her beast-taming prowess. A New Year’s Eve encounter underscores her avoidance of discussing SAO trauma with family, driving her to seek refuge in-game. Conversations with Kirito during this event reveal her evolving independence juxtaposed with unresolved emotional fragility. Post-SAO narratives trace her struggle to reconcile virtual loss with reality. During the game’s forced shutdown, she initially agonizes over abandoning Pina before discovering its preserved "heart," pledging eventual reunion. This mirrors her broader arc of tenacity and steadfast loyalty. Within the protagonist group, Silica occupies a younger-sibling role, offering emotional solidarity to figures like Kirito and Asuna. While seldom on battlefronts, she aids in collective conflicts when necessary. Design materials highlight shifting color motifs across adaptations, underscoring her thematic versatility without a fixed visual identity.