Half-elves (半寿族, Hanjijuu-zoku, lit., "Half-life Clan") or the Half-lived is a race of beings who are gifted with a lifespan that far exceed that of a normal human, but only spiritually, so their bodies can't follow and they behave unfittingly for their ages. Like their elven ancestors one of their main distinguishable trait is their long ears, which they cover using a variety of accessories.
Half-elves are known for their very slow aging process, but that unlike their elven relatives that only applies to their minds, so they have similar rate of aging compared to humans but their mental aging is a little delayed. So in other words, they are a race that age at the same pace as standard humans but their mental developement can't keep up with a normal human growing process making them act inappropriately for their ages and very hard to fit in society.
Due to this, they are being discriminated by the pure-blooded elves and some Harmonic Divine States like Tres España, were half-elves are very common unlike other countries. As such, they are oppressed, live in slums and sent to the most dangerous zones when war breaks out, with half-elves troops serving as shields in the front lines, oaring the galleys and dying without any accomplishments.
During the Battle of Lepanto and thanks to a unknown commander who became the "Hero of Lepanto" and later Tres España Chancellor and Student Council President, many of the half-elves were led safely through the hell that was that naval battle, famous for heavy casualities on Tres España side.