If Cassio do remain,
He hath a daily beauty in his life
That makes me ugly; and, besides, the Moor
May unfold me to him; there stand I in much peril:
No, he must die.
– William Shakespeare
Othello, Act 5, Scene 1. Iago’s jealousy of Cassio is highlighted here. The immoral Iago cannot bear human virtue and decides that Cassio’s qualities are too much for him and he must die.