Hello,
Grendel most likely refers to a character in the Old English epic poem Beowulf.
Grendel is a troll-like character who attacks the empire of King Hrothgar and his warriors. This demon seems abominable and unstoppable until Beowulf comes to the rescue of Hrothgar and with much struggle, eventually uses cunning tactics to lure Grendel to his death.
Grendel's ancestry is said to be traced back to Biblical times. Specifically, 'Cain' who is known for killing his own brother. This perhaps speaks volumes about the savagery that is inbuilt in Grendel's psyche, whom is capable of mass murder and destruction. There is said to be a psychological emphasis in the purposeful affiliation with the biblical Cain. It evokes our judgements (as the reader) of the monster and forces us to draw a moral compass, in which depicts this pagan character as 'wrong' or 'evil.'
I hope this answers your question.
