Heart of Iron (Fate AU)

After a brush with death, young Shirou Emiya ends up in the realm of the fae, trapped far in the past. With his body changed by magic, and the way home uncertain, he will have to forge his own path. But after centuries spent in Faery, cut off from the rest of humanity, can what emerges still be called a human, or will he succumb to his new nature? Fairy!Shirou AU.