A Surly Dog
Jaded
Sellfish
Calloused
Negative

I liked selecting words from each definition... it seemed more descriptive than their definition: Given to sneering at rectitude and the conduct of life by moral principles; disbelieving in the reality of any human purposes which are not suggested or directed by self-interest or self-indulgence; as, a cynical man who scoffs at pretensions of integrity; characterized by such opinions; as, cynical views of human nature.