You Can Keep The Scarf (слэш)

Written for this prompt.
tl;dr: Thor encounters a crying Jotun and believes he has laid eyes on the most beautiful sight in all the realms. Promising to return and leaving his scarf as a reminder, he returns to Asgard only to be forbidden to return to Jotunheim. Years later, Thor finally meets Loki again only to find that the boy has grown into a man, and has become more beautiful than before.
Inspired by this lovely piece. Credit to kleinkonan.