As the story unfolds, Roderigo becomes a pawn in Iago's schemes. Iago manipulates Roderigo into providing financial support for his plans, and convinces him that Othello has been unfaithful to Desdemona with Cassio, Othello's lieutenant. Roderigo is easily swayed by Iago's words and becomes consumed by jealousy and anger.
In his desperation, Roderigo agrees to help Iago in a plot to kill Cassio. However, the plot fails and Roderigo is mortally wounded by Iago. As he lies dying, Roderigo finally realizes that he has been used and deceived by Iago, and he curses him for his treachery.
Roderigo's role in the story serves to highlight the destructive power of jealousy and manipulation. He is a character who is easily influenced and manipulated by others, and his downfall is a consequence of his own flaws and weaknesses.