Broke guy allows flirtatious friend to have sex with his girlfriend for cash

A young guy is in a tight spot financially. His girl is out of town and his friend, who has a penchant for the ladies, offers to help him out. The friend flirts with his girlfriend, leading to a heated exchange between them. The friend then proposes a risky plan - he wants to have sex with the girl in exchange for cash. The guy is hesitant but desperate, and eventually agrees. His friend goes to his girlfriend's place and persuades her to give in. She's initially taken aback but eventually gives in. The friend wastes no time, and the girl finds herself being pleasured in ways she's never experienced before. The guy watches from afar, a mix of shock and arousal. The friend leaves satisfied, and the guy is left with a new perspective on his relationship.