There is a request that becomes available starting in chapter 1 that unlocks the gloryhole. Start it in the tavern by speaking to Roland, then use the journal (hotkey E) to get through it. There’s a few ways you can complete it, but all unlock the same rewards, including the gloryhole activity.
The traits menu shouldn’t let you even see the traits related to using the gloryhole unless you’ve unlocked it, so I should look into that.