Gibrillont asks you to deliver the wine to a monk who serves the most impoverished denizens of the Brume.
This quest is available if you have completed the quest Noble Indiscretions.
Starting the Quest
Talk to Gibrillont in the Forgotten Knight in Ishgard to begin the quest.
Deliver the Twice-Mulled Wine
Go down the stairs in the Forgotten Knight and go outside. Go down the stairs to reach the Brume, then go to the quest icon on the map. If you are having trouble finding it, go to the Brume Aethernet Shard and go east, and look to the north as you go east, and you will see Gerraldieux in an alcove. Talk to Gerraldieux and hand over the Twice-mulled Wine.
Report to Gibrillont
You can either go up the stairs near the Brume Aethernet Shard, walk along the stone wall, and go up the next set of stairs to reach the back entrance of the Forgotten Knight, or you can use the Brume Aethernet Shard to go to the Forgotten Knight Aethernet Shard and go through the front door. Then go to the quest icon on the map and talk to Gibrillont to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Gibrillont to accept the next quest: Bloodlines.