Your sister is a genius! But it's unfortunate that all of that mental energy goes to making her life easier or her body fatter, usually both at the same time. Her chef bots are selling well, though you doubt anyone else has three actively cooking at all times to keep them fed. Let alone developing a weight gain pill on top of that.

Your new job begins soon! Make sure you lock the door on your way in, and please don't tamper with the animatronic girls. They have been known to become quite arousing.

One night, your fiancée Pearl wakes up super horny, but it seems something different is coming. Something bigger is coming. A demon 'in training' is looking for some fun, and you and your fiancée are her new targets.

In an attempt for a speedy personal project, your succubus partner steals a spell-book from the forbidden library, and wants to try out some growth spells, soon starting her breasts and butt growing and swelling out as you begin to fuck on the bed.