"A Catholic is just as capable of evil than anyone."
I think this is a solid thesis for an essay about Graham Greene's 1938 novel Brighton Rock. I might substitute another word for "confused," such as conflicted or even warped. The protagonist of the novel, 17-year old knife-wielding Pinkie, is a singularly unpleasant lead character: a petty gangster who identifies as a Catholic and is in a relationship with another 17-year old, the sweet, but somewhat passive Rose.
Pinkie is indolently contemptuous of seemingly everyone and everything around him: "Was there no escape—anywhere—for anyone? It was worth murdering the world" (92). His religious beliefs don't seem to influence him at all, as he's a criminal and a killer. The only real evidence of his Catholicism is his guilt and self-loathing, a common feature in Greene's protagonists. And he eschews drinking and smoking, which seem like minor vices compared to his murder of Hale. Maybe the most Catholic aspect of the novel is its strong sense of good and evil.
There are only two female characters in the novel, Rose, and Ida, a heavy-set woman who is a witness to the murder. Rose is devoted to Pinkie, telling him "you're sweet to me," but their relationship doesn't make much sense, and Pinkie treats her in a dismissive manner. You could certainly discuss Greene's own life and views in relation to the novel. He was a Catholic but an idiosyncratic one, who had multiple affairs and drank heavily. It's also hard to think of too many well-developed, three-dimensional female characters in his work.
Consult this website for further reading:
*I'm using the English Penguin paperback edition.