I'm Being Blackmailed By My Cleaner

I have something embarrassing to admit: I'm being blackmailed! Mrmrglmr agreed to clean some of my things, and got hold of my spare murloc costume. He's threatening to reveal my true nature to the other murlocs. I need not explain to you what a disaster that would be! Besides, I have a plan that's going to require that we get that costume back. Please, <name>, go to Mrmrglmr at the other end of the Retreat to the north and do whatever he asks of you.