Lex Luthor - Superman Vol. 2 #9 (The Waitress Scene)
The infamous "Waitress Scene" featured in Superman #9 (Vol. 2) shows the real depth of Lex Luthor's cruelty. Aware of the influence that money can have over people, Luthor offers to help one lucky waitress resolve her debts and live a better life. Luthor tells the waitress that she must come live with him and, in return, he will take care of her financially.
The waitress ponders her decision and then, deciding to side with Luthor, runs out to the agreed upon meeting spot... but Luthor was never really waiting for her at all.