I love your sprite art style would love to know how you do it! I played the game all the way through with Sophia (I say is best girl) I like the layout of the game mechanic but I feel like they could flow together a little better.
One the changes that would be cool would be for the stat Self-control to affect eating speed & stamina as it would represent the girl's pull to eat growing stronger & stronger turning them slow into a eating machine, the Self control stat decreases automatic with each new weight level.
The next stat I think that also could use a change would be Fitness as is would be cooler if it was link to stamina, as the girl workout to build muscle to have more energy to feast they would have their max Metabolism increase as a trade off for the energy boost. So the player would have to try to balance stamina with fitness to keep the weight gain train going.
Plus the is could sweet to have there weight level to boost there total Metabolistic needs to as well to make a bit more of a challenge to the weight gain train with their being a risk if you have not got the girl's Self-control low another with or feed them stead stream of calories that can go down a weight level. Could lead to some interesting event scenarios on how the girls respond to your neglect.
I almost forgot, I would be cool if Charisma would reduce the cost of hangout's by costing less Affection as one's character builds up there Charisma
And it seems the girls stomach capacity increases in size is not based on how close they are to Max fullness but calories they consumed (at as far as I can tell).
sorry if it's a lot, I got to many ideas running around in my head.