The elder Princess Royal of the Elesius Kingdom in Wild Arms XF and Katrina Elesius's older sister, who is presumed dead after a landslide. Alexia cannot communicate with Filgaia's Guardians, so she had to be removed from the line of succession. Clarissa Arwin almost looks like Alexia's twin, so she impersonated as Alexia until it was revealed the princess was alive and in captivity.
Even though Alexia and Clarissa look almost alike, they are NOT twin sisters, so the 'twins' tag shouldn't be used. To tell the two apart, Alexia often has short blonde hair, wears a pink knight's outfit, and wields a sword.