Lostvayne

The Demon Sword, is a sacred treasure belonging to the Dragon's Sin of Wrath, Meliodas.

Appearance
Lost Vain takes on a form of a curved shortsword with the Dragon tattoo emblem into it with five holes on the sharp blade.

Abilities
The abilities of Lost Vain have yet to be seen.

Trivia

 * Lost Vain is the fourth Sacred Treasure to be revealed in the series.
 * Lost Vain worth 50 gold pieces as it was sold in a market in Camelot.