"The entries don't have to be highly polished, but they do have to be smart and honest," it said on Facebook.
Several people have questioned the appropriateness of Massive's cover.
"Are you raising awareness of the topic or are you trying to attract drama by perpetuating a harmful stereotype about sex work?" asked one woman on Facebook.
"I'm sick and tired of media that portrays sex work as a dichotomy between female 'victim' and male 'violator'."
Another person commented saying they found the image disturbing.
"Not just the barely dressed woman in a position that is degrading, but added to that, the violence with the iron fist grabbing the hair -- and the sad pleading eyes -- I find it a most disturbing image."
Massive editor Carwyn Walsh has stood by the cover, saying it went with the story.
"When you read the story it's about students involved in the sex industry telling their own stories, so it is relevant to that," he said.
However, Massey Wellington Student's Association said they felt the image was inappropriate.
"We have student welfare and safety as out priority and believe that this image could be incredibly offensive and triggering for many students and as it is on the cover, we are concerned at the fact that students cannot protect themselves or be warned about the graphic nature of the image."
The backlash followed an incident last week when Victoria University student magazine Salient was forced to publish an apology after printing a satirical interview with its chancellor, Sir Neville Jordan.
The piece included fictitious lines from Sir Neville saying the best and worst part of his job was "shaking lots of sweaty hands at graduation ceremonies".
Sir Neville said the piece was "disgusting" and "a travesty".