Since Debbie has come to be a major focus point of the comments currently, I think I add my two cents as well. I like Debbie and am glad that she is part of the game. That said, I theorise, since as of this moment the game is still at the beginning, that Debbie will have differing personality across the 3 paths as will be her impact.
On the Sharing/swinging route Debbie will probably be a nice girl, liking the MC without hidden agendas, maybe becoming the catalyser for the MC pair´s starting of sharing and/or swinging.
On the cuck route this might be mostly true too, but there will be more tensions all around. On the NTR path I see Debbie as a major disrupting force (willingly or not).