Astaroth #1 - under Astaroth's hammock in the Glory Dungeon tower in the morning [Astaroth affinity #3]
Astaroth #2 - in the main area of the Glory Dungeon in the morning [Astaroth affinity #3]
The 4th beer is probably the Christmas one for the Twins. To see it, finish the Twins' affinity stories (only 1-3, declaring love isn't necessary for this), then set your device date to December 25 and go to the tavern.