Elwyn

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).

There are subtle hints that Elwyn harbors romantic feelings for Zero (also known as Xion), which may be reciprocated. Additionally, she shares a mysterious bond with Xecty.
Note: While the Japanese version refers to her as Elwing, the official English translation uses Elwyn.