This achievement is won within Molly's story, which is played by interacting with her diary on the dresser.
When you find yourself on the ship as a tentacle monster, make your way along the ship and up to the second floor. After you go through the double doors, you will hear the sailor singing 'What shall we do with the drunken sailor'. Don't attack him until he finishes his song for the trophy. Note: he does go on for quite a while so be prepared to sit and wait for a couple of minutes.