I know what you are
A stupid twist on 'that's what she said.' You act like you're super smart, but really you're just twisting what someone said to make it about you.
He said, 'I know what you are,' like he was reading my mind and I was dumb.
She said it like it was some big secret, but I knew she was just being weird.
He texted me, 'I know what you are,' like I was the one making the joke.