George
George is the eponymous "Single Man" of the novel's title and rather a victim of being born in too early of a time. Place George in the present day and he would likely be happier, fulfilled and unlikely to be feeling suicidal. George's circumstances are that if a person forced to hide the most intrinsic thing about themselves for fear of retribution. George is a gay man at a time when being a gay man meant social death at best, and trial and imprisonment at worst. George is originally from England and has now relocated to California where he is a college professor. He has just lost the love of his life, Jim, suddenly, in a car accident. His heart is broken and he feels here is no point in living. When we meet him it is on the day of his planned suicide. He plans on going the rough the motions of the day but because of his decision to end his life discovers a heightened sense of awareness in everything and finds that people with whom he has contact who on any other day would not affect him much at all are suddenly instrumental in pointing out a purpose in life.
George is essentially a very reliable man; he has dinner plans with his friend Charley, one of the few female lovers he has had in his lifetime, and keeps them, postponing his suicide until after the meal. George is the kind of man who has such a steady moral compass that he would return a library book before killing himself to avoid it becoming overdue. George's life is a life plagued with ironies, the biggest one of which is that after deciding he must live and abandoning his plan to commit suicide, he has a serious heart attack and dies in his bed, still so devoted to Jim that his lover comes to greet him as he crosses over.
Jim
Jim is the most important person whom George has ever had in his life; he is George's lover. Jim is comfortable with his sexuality but unfortunately his parents are not and thus his relationship with George and his relationship with his family are compartmentalized. His parents don't acknowledge that he is gay, or that he is in a committed relationship, or that he has a partner - they do not even invite George to Jim's funeral. Although the reader does not meet Jim in the novel in the present he is nonetheless a key character whom we get to know through George's memories.
Charley
Charley is one of George's oldest friends and one of his few former female lovers. George loves Charley deeply - as a friend. Charley loves George just as deeply but in a far more romantic way and seems frequently weary of his "it's not you, it's me" reason for not sleeping with her. Although Charley accepts George's sexuality in a non-judgmental way she is nonetheless angry with him for being gay in the first place because it prevents him from having a permanent sexual relationship with her and just lately it prevents him from considering even the briefest of flings. When given courage by alcohol Charley has a tendency to brooch this subject and taunts George for missing out of a wildly fulfilling sex life with her because he wants to be with a man.
Kenny
If there is one person who is pivotal to George's change of heart about his suicide, it is Kenny. Kenny is a student who is in a class that George teaches. He finds that one of George's lectures has really resonated with him; George has spoken about guarding against being ruled by fear and Kenny has taken this to heart. He is attracted to George and invites him for a drink but is politely turned down . When they accidentally meet at a bar later, Kenny asks George to accompany him to the beach and this time his persistence is rewarded. Although his clumsy attempt at seduction fails, Kenny stays to talk to George and is present when George dies from a heart attack.
