I don't think Salah cares about loose skin when Chantal loses weight because even if he does find her attractive, I don't think he's sexually-driven. If he wants sex he can just bend her over like Nader did and ignore the odor as best he can, loose skin or no loose skin. I think he wants her to lose weight so that she isn't embarrassing to be seen with. I know Chantal seems to think that wearing a burqa means no one can tell how fat she is but the truth is that she is an enormous, waddling blight. Even in a very fat nation like Kuwait, her fat distribution and overall size still make her an anomaly. The Muslima larp garb can't hide how fat she is but it can hide lots of loose skin.
But all of this is sort of weird because if he has a vested interest in her losing weight, it means he intends to be around her for a long time, or least long enough for her to lose weight. So whatever it is he wants out of Chantal isn't going to be a short-term gig.
Unrelated, has anyone noticed that Chantal has said "butt" several times since the infamous nudge? I know the general consensus is that Salah is a controlling dick, but maybe not. I mean, he's controlling by liberal Western standards, but I think even if he had an idea of how Western women raised without the specter of Islam scaring them into compliance behave, Chantal was still too much initially and he reflexively reacted when she behaved outside the very specific norm he was used to. He grimaces at her, talks around questions he doesn't want to answer, and can't control the occasional look of disgust, but she's Chantal. She's a lot to deal with, cultural differences or not. He's essentially training an old fat dog new tricks and who among us wouldn't end up swatting her on the nose with a rolled up newspaper several times a day if we had to live with her. Not saying he's not a dick, not implying he is entitled to physically correct her, but I am saying I don't sense genuine abuse here. She's already pushing certain verbal boundaries and he seems to be getting used to it.