The Decameron LWB is one of the few I didn't throw away... but the spread is confusing as hell....
..D.D.D..
B........C
B..1.2..C
B........C
..A.A.A..
Cards 1 & 2 represent the lovers, "in bed." After a long-winded discussion of ettiquette of men and women in bed over the ages in various cultures, they establish the man is Card 1, and the woman is Card 2. But whatever.
At their feet (A), these cards provide info on "how the couple appears, the aspect it [the relationship?] has assumed, and judgment which has spread within society.
At the man's side (B) and the woman's side (C) are three cards to clarify what each partner wants, or desires.
Above their heads (D), are "three cards...which, turned over last, will respond to the questions and interpret the final destiny of the amorous relationship." I don't know what "respond to the questions" really means in terms of a spread (a bit vague). I reckon it's best thought of 3 cards as outcome/advice for the couple.
Hope this helps!
(All quotes from the Decameron LWB, text by Spadanuda (?))