She's not plump, she's just got a little bit of a roll there. Could even be excused by simply a too tight bikini.
There's *maybe* two or three pounds there. I wouldn't say 'plump' until she's got a good fifteen or twenty, minimum.
Sheesh, anorexic models skewin' everyone's ideas of thin...EAT A SANDWICH! NOT being 98 pounds won't kill you and it won't ruin your career, no matter what you think!