Iago is lecturing Roderigo with an evil smirk on his face, but Roderigo is only partially listening to him while rolling his eyes at how enthusiastic Iago is.
Iago calls out the Brabantigo, and have a conversation about his daughter. Rodrigo has minimal input in the conversation but sometimes adds in with an uncertain, high voice. Iago phrases everything respectfully but his tone is sarcastic and hissing without pity.
Brabantio comes down in his night-gown with two servants. Iago continues with his smirks and nasty comments while Roderigo gains confidence. Brabantio becomes angry, starts yelling and orders everyone around.