The Petnis is a big pet penis for premium users which will accompany you as you walk around the MnF island. You can buy a Petnis for $3,000 at the Petnis Shack, choose one of many colors for it and give it its own name. If you have the desire to change the name and/or color of your Petnis, you can go back to the Petnis Shack and for $500 change it. The Shack owner Marissa will also demonstrate you what the Petnis is for if you pay her $300.

You cannot remove the pet once it has been bought, however you can 'hide' it by clicking on yourself to view your stats; on the right above the Petnis there is a tick box named "Hide Petnis", clicking it will refresh the area you are in and you Petnis will no longer be visible following you around though people can still see it if they click on you.

With the Petnis you can fuck the following NPCs:

As of the most recent update petnis's can now be used during sex by selecting the "Petnis Fuck" pose. If selected by the woman in male on female sex this will cause the female character to be fucked with her own petnis while the man watches however if selected by a male who possesses a petnis his will be used instead.

In lesbian sex when selecting the pose the other player will be fucked with your petnis instead.