https://www.amazon.com/dp/B0839GSDMG
Sara and Dani are roommates on different trajectories in life. Sara is an introverted IT specialist who loves producing manga and Dani is an outgoing free spirit. Their worlds become increasingly intertwined as Sara struggles with her image and secretly obsesses over her roommates gorgeous body. A chance discovery allows Sara to project her ideals of the perfect body on to her friend while regressing back into her old habits and in the meantime, finding a way to profess her secret love for her.
This is an attribute projection feeder tale featuring breast and posterior expansion and weight gain and features FF intercourse.