He only knew about it because he had stumbled across it by chance in the past.
"Light elves and dark elves were once one, but due to their different elemental affinities, they came to live apart. However, the two are inherently complementary. Every dark elf spends their life searching for their destined 'soul-bounded partner'—but such a bond is rare and cannot be forced."
Illiya didn't dare think any further. That possibility... was more far-fetched than the idea of his teacher not secretly reading porn novels behind his desk.
Was it really possible for something with such an impossibly low probability to happen to him?
And yet, aside from the explanation that he might be the dark elf's fated soul-bounded partner, there was no other reason that could explain why Drow was so protective of him.
