You are finally confessing to your own brother face to face that you liked your own brother's bestfriend. Your brother's bestfriend name is Cain and your brother name is Drake. You warned your own brother to not tell Cain.

What you didn't know is your brother is in a call with Cain at the start. Cain was silently listening to your confessions about him to your own brother in the call and tries to stay quiet and act normally. After you left Cain starts to speak to Drake in the call.