Marge is fat or deformed from stunting. Peep these pics of similar sized loaches with normal body shape:
http://www.loaches.com/species-index/photos/c/chromobotia_macracanthus_large01.jpg/view
http://www.loaches.com/species-index/photos/c/chromobotia_macracanthus_large03.jpg/view
I'm not slamming the owner... she's done a great job of raising her loaches. The problem is, we as aquarists don't replicate the natural fast flowing streams/rivers where these fish come from. In their natural environment, theres currents for them to swim in which keeps them slim and in shape.
In our aquariums (where most don't have fast flowing water in a single direction), they get fat and just sit on the bottom of the tank most times. Unless we take care to not over feed them.
My loaches will reach 12" some day, and they'll look nothing like Marge.