F is for Fafnir
Fafnir lived in the Germanic world of giants, dwarves, greed, and deceit. Oh yeah, and of dragons. When fan-fave Loki killed Fafnir's bro, Loki had to compensate the misdeed by filling the corpse with red gold (or something silly like that). Alas, the treasure was cursed and caused all sorts of greed-fueled intrigue - eventually leading to Fafnir having to turn into a tremendous dragon to guard the gold. Faffy was eventually slain by the hero Sigurd.