Sherlock Holmes and Erin Adler were the two main characters in Sherlock Holmes. Holmes was a clever, witty, and calm detective, and Erin Adler was his loyal friend and assistant. Erin Adler was a smart, brave, and upright man. He often provided useful advice and help to Holmes. During the investigation, Holmes often needed Aaron's help to deduce the criminal's motives and actions. Although Holmes and Aaron were close, their personalities and backgrounds were very different. Holmes was a high-income aristocrat while Aaron was a poor working-class man. This huge gap led to misunderstandings and quarrels between them, but in the end, they still became best friends. The relationship between Sherlock Holmes and Erin Adler was a unique and complicated friendship. The mutual support and help between them was one of the important topics of Sherlock Holmes.