(Click the character infographic to download.)
Wiglaf is a young Geatish warrior in Beowulf's retinue who follows him to the barrow where the dragon is lurking. When all of Beowulf's other thanes, or lords, abandon him, Wiglaf remains loyally with his king, encouraging and supporting him:
And now the youth was to enter the line of battle with his lord, his first time to be tested as a fighter. His spirit did not break and the ancestral blade would keep its edge, as the dragon discovered as soon as they came together in the combat. (2625-2630)
It is only with Wiglaf's help that Beowulf is able to defeat the dragon—Wiglaf's timely sword-stroke gives Beowulf the opportunity to stab the dragon in the side and kill it once and for all. As Beowulf is dying, he gives his golden necklace, called a torque, to Wiglaf, probably symbolizing the transfer of power from the dying king to his chosen successor... even though Wiglaf would rather have Beowulf around than his silly ol' torque:
"As God is my witness, I would rather my body were robed in the same burning blaze as my gold-giver's body than go back home bearing arms. That is unthinkable, unless we have first slain the foe and defended the life of the prince of the Weather-Geats. I well know the things he has done for us deserve better. Should he alone be left exposed to fall in battle? We must bond together, shield and helmet, mail-shirt and sword." (2650-2660)
Wiglaf represents courage and loyalty in the face of unbelievable odds. In fact, he's a sort of a reverse-Judas figure. Whereas Judas is the only one of the twelve apostles who betrays Jesus, Wiglaf is the only one of eleven thanes who remains loyal to Beowulf. The implication here is that, even though cowardice and betrayal are immoral, in the world of Beowulf they are far more common than true courage, loyalty, and indifference to death and suffering.