Grendel and his Influences

Grendel is a creature of is environment.  This very human trait plays a major role in his character.  He grew up wanting nothing more than to be loved by a creature who couldn't communicate her love even if she had it.  At the very least she showed she cared enough to protect him, but he projected much more onto her.  This shaped him, just as the dragon and singer would eventually.  

Grendel simply wanted to know who he was and where he came from, something (like her love) his mother could never directly express to him.  The singer gave him some sort of answer.  He implied that Grendel was borne of Cain; Grendel interpreted the meaning of the song that he was eternally, unforgivably, and incurably evil.  When you're told time and time agin you're evil, you're bound to begin doing evil things.  

Grendel's visit to the dragon is in sharp contrast to the words of the shaper, however.  The dragon's nihilistic approach and worldview are stark in comparison to the defined and meaningful picture the singer painted.  In Grendel's mind these two things must have clashed greatly, and of course he prefers the dragons explanation as it doesn't (literally) demonize him and provides a certain justification for his future actions.  His meeting with the dragon also allowed Grendel to experience true fear, however, which also shapes the way he feels about the human and develops depth within his character as he is deeply conflicted with what he needs to do in his short and likely meaningless life.