Ginger sex scenes have bed background with 2 available blanket colors, neither match Player's bedroom blanket color. But I would not bother about such little discrepancy. Most of original HTH scenes don't have proper background for places where they take place.
Currently dialog does not support switching background while in dialog, but allows travel - leaving dialog in different location.
If we wan't to add Ginger to Player's room, then it can be either main room where other 3 characters appear. Involves adding Ginger sprite to that place. Or it can be in the bedroom - involves adding sprite to that bedroom, likely some incomplete scripts fixes for Player's room and also bedroom background for dialog, that does not exists yet.