Okay but guys, i know that Desdemona and Cassio have limited interactions but they're best friends. I don't make the rules, Shakespeare himself told me this. I refuse to believe they don't speak seeing as Cassio would be with Othello pretty much all the time. She offers to vouch for him because they're very close and he gives her updates on whats happening in battle and at court. He's kinda like her branch into the outside world outside of her duty for her husband idk