Ought to be thy Adam.

“Remember, I am thy creature; I ought to be thy Adam; but I am rather the fallen angel, whom thou drivest from joy for no misdeed.” (Shelley 53).

This is reference to Paradise Lost, which the monster mentions he has read on page 111. The fallen angel is Satan, who has no joy, excepting that in others’ despair and destruction. By saying “I ought to be thy Adam,” he means that Frankenstein should be taking care of him as God did for Adam. (http://www.answers.com/topic/paradise-lost)