Harlan is Tom Bradshaw's wealthy best friend who lives in the city, and is the boss of Long and Whitney Law Firm.
Tom Bradshaw is one of Harlan's closest friends. In season 2, Harlan manages to finally persuade him into leaving his beloved law agency and working for Long and Whitney instead, knowing that Tom is a fantastic lawyer. Harlan is known for often trying to wingman Tom by trying to introduce him to various women, and even taking him out specifically to find women. Whenever Tom is lost with women and doesn't know what to do, Harlan is his go-to man for advice and general help & support.
Harlan and Larissa started their relationship via various sexual encounters. They are shown to be very adventurous with their sex life, even participating in a threesome with Samantha. Harlan eventually proposed to Larissa in season two to which she said yes. Albeit Larissa being sad to say goodbye to single life, she found a way to make the idea of a marriage with Harlan work for her. Being scared that marriage would make her lose herself, Larissa wished to keep her apartment and not move in with Harlan, much to his dismay. She confessed this to Tom, who was acting as their lawyer and drafting their prenup, whilst in a brief argument with Harlan, and the situation was flattened out when Tom suggested that Harlan buy her an apartment adjoining his own on his floor. The two of them got married in the Finale of Season 2, at an Airport.