Can't seem to trigger the wine merchant appearing, is there anything else in the game I'd have to do for it?If you have "Sweet Lips" in your inventory keep using the Chat option with her untill the specific interaction triggers... Kinda stupid but the Dev made it one of many random chat's you can have with her.
If your Affection is not 40+ already it will just end with you getting +10 affection. even if you are at 39 the scene won't trigger you have to be already over 40/41 .
If you don't have sweet lips wine go to the Elf camp during the day time and buy it for 50 gold from the wine merchant there.