Akiko has had a few CMOA, but her most recent was putting the audience in their place during Mamiya's fight against Yuuto in Chapter 189 as they practically chanted for the boy to give up. Her anger was so surprising that it caught a raging Nana off guard, who was just seconds from beating the crap out of the Jerkass in front of them.
Akiko: What's wrong with being stubborn? Even if it's lame, even if it's uncool, you don't give up until the very end. What's wrong with that!!? Shut up and watch, morons!!