What's wrong with a girl wanting to look healthy? She's amazing, but she's definitely overweight, and she shouldn't be proud of it. It's really great to see her transform in the future and how much more confident she will become, we all love her already, but most people want to have a healthy version of her. She's my favorite character but she won't stop being cute if she loses weight. Adele was insulted by idiots on Instagram after her weight loss, why isn't she proud of being fat? Why should she lose weight? These are crazy people who can't be happy for her. In general, being fat is bad, but to pull yourself together and put your body in order is a reason to be proud of yourself, and we are not talking about beautiful curvy forms, wide hips, big breasts and a big heart shaped ass - it's all beautiful, but Emma does not have this, she is just an ordinary overweight girl who hasn't bloomed yet. Anyone understands that eating well and going to the gym is great, but sitting at home and eating chips is not great, no need to be lazy
I know you didn't mean to say this, but "shouldn't be proud" and "being fat is bad" is such a flippant way to describe a fictional character's body type and life (or a real life person to be honest). I'm not saying being fat is healthy, nor is it abhorrent to be skinny. The issue that I have is that the character was created with this shape in mind. Healthy? This is a GAME! Only the author can make her have adverse health conditions. I don't see this a problem at the moment.
I don't know why you added the real life Adele aside to this discussion when Adele is a real life person. We all know real life people can be dicks online; also good for her for losing weight! But these things are NOT the same. Losing weight is very helpful: for real life people. Have I said "real life" enough times? Damn, now I'M being flippant.
Being fat is not bad, it can be unhealthy which can lead to bad things. Being grossly overweight is bad. I doubt that even if there was a risk of Illness from this fictional world, Emma would even come close to having real health issues. I have plenty of relatives that are very healthy but are overweight because of their metabolism. They have to go to much more limiting diets and more exercise for them to look "healthy" by your standards. But they gotta work so they don't have time to squeeze in exercise between child care and sleep.
I'm not saying the dev can't change Emma. My thoughts are, I'd prefer he doesn't. It's good to see a slightly bigger girl in a VN. This is something that would make you happy because there are fat people in "real life!" (I'm being flippant again :/) Like I said earlier, I feel you were off base by condemning "fat" people for their dietary choices. I'd rather date a fat person with a good sense of self, a fulfilling job and/or a great personality than one that is just "healthy." People are fat all over the world, just cause it's unhealthy doesn't mean they don't live their lives. I'd rather Emma stay a character that reflects a person that doesn't have to be skinny to have a higher self esteem. The MC prior to death also wasn't super skinny nor is the mother. I know I wouldn't look down on my kids/friends for being fat, nor being skinny as a matter of fact.
Lastly, I know I kind of went off on you, but honestly, what you said was really insensitive in a weird way. I'm not even saying you condemned fat people, and I'm not sensitive by nature, but man, I could feel the indifference in your words. Didn't like it.
Regardless, I wish you a good day!