Who are they? Where did they come from? Does it matter? No.
After losing Kazanova, Archer goes on a booze-fueled sexual rampage around the world. While on an island in French Polynesia, he ends up in bed with a red-headed newlywed, who can’t remember the previous night. Her husband sounds like a total dick, though, so it’s all good.
Archer encounters Rita (a nurse) while using his alias Chet Manley. They proceed to get down behind some hospital equipment, after which Archer forgets her name.