This trophy will unlock upon completing the following side missions, which can be found in the main island and in Flood Town:
Taking Out the Trash (as part of "Karma's a Bitch" story mission)
"Taking Out the Trash", is part of the "Karma's a Bitch" story mission, when Zeke introduces you to side missions. These missions require you to hunt down certain individuals by matching the person with your photograph. These side missions serve as a mini sidequest and are linked together so you'll know it when you activate these missions.
Note that these side missions are labeled as Bad Karma opportunities , so unless your karmic rank is maxed out as Hero on your good playthrough (karma won't change if its maxed out), consider doing these on your Bad Karma playthrough instead.