Captain Holt: Interesting, you two are sure you want to be involved with this?
Rosa: Investigating O'Sullivan? Yeah, that dude sucks. He tried to blackmail me.
[flashback:]
Frank O'Sullivan: If you don't stop harassing my officers, I will release proof that you are bisexual.
Rosa: Already came out.
Frank O'Sullivan: Oh, come on. You can't blackmail anyone anymore.