I would agree that Beowulf is the true hero (and the main character) in the story. This epic tale speaks about Beowulf and his willingness to fight a foe far greater than himself. He even goes into the monster's lair, alone, to do battle. He fights Grendel for many reasons, but in the end he does it because that is who he is. If he does not defeat Grendel many people will die.