Sir Simon, also known as the ghost, is one of the main characters in the story, "The Canterville Ghost." One of the strongest impressions of Sir Simon is that he has criminal tendencies. When he was alive, for example, he murdered his wife, Lady Eleanore, in the library of Canterville Chase because she was "very plain" in appearance and not a good housekeeper.
In addition, Sir Simon is very proud of his earthly achievements. This is supported by his affections towards the suit of armour. He proudly recalls how he wore this at a tournament in Kenilworth and that Queen Elizabeth I, the Virgin Queen, had complimented it. This feeling of pride also extends to his achievements in the afterlife. He is gleeful, for example, when he recalls some of the people he has frightened at Canterville Chase. He appeared to the Dowager Duchess, for instance, by placing his skeleton hands on her shoulders as she dressed for dinner. She was so terrified that she fell into a "fit" for some weeks after. Similarly, Madame de Tremouillac was "confined to her bed for six weeks" after Sir Simon appeared to her as a skeleton while reading her diary by the fire.
But Sir Simon exhibits vulnerabilities, too. He is easily hurt and humiliated by the Otis family, for example, when his attempts at scaring them completely fail. The twins fire their pea-shooters at him, Mrs Otis offers him a tincture for his throat and Washington hems him in with a "garden syringe." Despite donning his most infamous and scary costumes, he cannot make them frightened of him and this causes him to experience a deep depression.
But this depression leads to the story's climax because it forces Sir Simon to confront his bad deeds and seek redemption in the Garden of Death. To do this, he successfully appeals to Virginia Otis who follows him through the wall of the Tapestry Chamber. There, she sheds tears for Sir Simon and he is granted the gift of eternal rest.