Hypothetically if Obi so gained weight from all the extra food he fed them would be get off to that. Id feel liked he'd get off to it.
That intimate feeling of knowing there's more of your so kiss, bite, suck, and nip at. And it's all thanks to him, no one else. The thought would have that man drooling.
I can feel it in my bones.
On the one hand, Obie is the brighter side of associating food with love. Morell would be the darker side. Obie feeds you because he loves you, because that's how his culture tells him to express love. A glutton knows his partner will be happy with them forever if they're always well fed. If they're stuffed. And, well, Obie is bound to cook a lot more than you'll ever need to feel full, because he forgets a human's appetite is nowhere near a gluttony demon's near endless craving. That was entirely accidental on his part.
When the weight gain starts, if it does, Obie gets a rush. It started out as something truly wholesome- He was happy to see your body full, taken care of, beautiful! Not that you didn't look beautiful before, you did, this is just a differently gorgeous form of you, one that he helped create. What began as admiration and infatuation, pride, very quickly turns sexual.
And well, feederism is fairly vanilla among gluttons of all sizes. It's part of their core. Most of the ones who seek contact outside of the gluttony ring just learn to be a little more subtle about it. That's why Obie never really spells it out to you either. Because it's honestly better if you don't think about it too much, right? Just enjoy his care, yes?
If you gain weight, and it doesn't bother you, then there's no reason to panic, right? You look so unbelievably hot, Obie wants to touch every new inch of you and mark it. You're a deity among mere peasants and he's the only one lucky enough to get to maintain your luscious body. You will feel like the most attractive creature to walk this Earth and Obie will make sure everyone else knows it.
Best of all, the demon takes the time to make sure you know he's not merely fetishizing your weight. You're a person, you're the human he's fallen deeply in love with, no matter what shape your body takes, he will crave you to his grave. Foodplay and feederism are things Obie will suggest but never impose on you, unless he's truly lost, but I digress.