Seems it's not just a website. They built an app called also DEM Market. According to virustotal the app is safe but i think someone experienced enough has to tell more about this app.
OP didn't tell anything about the app or the smart-contract which also need to be vrified before inviting people to use it. The idea seems to be original but how to convaince users that they can exchange illegal stuff in the internet in a secure way? Users choose Tor as the best trusted tool for anonymity, so why they have to choose your market.
About the website, there is litterally nothing except some few available trades.