Azarthes said
What about making your interest/SO/spouse fat to lower their self conscious and then gettin' them on a diet to redeem their hot points? Surly that would be a good bet, then you get to cash in on 'you stuck with me through my fat phase points, i love you ^^' points.I think you're missing out on a big goldmine here.
Alternatively, get them fat to lower their self-confidence and then bag them when they're at their "weakest."
If you're into that kind of thing. But you shouldn't be.
However, this has the potential to backfire if they get hot again. They might view you as part of the Fat Phase and toss you out along with their excess skin, so they're not reminded of their shameful past.