Elwyn is a courageous yet occasionally childish princess of Fontina and a member of the Elf race. An old friend of Zero, she shares a complex history with him and has even warned that she would kill him should he misuse his powers.

Elwyn travels alongside Souma, who is able to draw a soul blade imbued with lightning properties from her—the Wind Thunder Sword Blitzbringer (風雷剣 ブリッツブリンガー, Kazeraiken Burittsuburingā).

Note: While the Japanese version refers to her as Elwing, the official English translation uses Elwyn.