Apparently this is one of those few instances where Chelsea doesn't seem too jealous of someone else's preposterously-proportioned posterior (in this case, Elma the catgirl's magnificently phat bum), even when they playfully (and emphatically) booty bump with Chelsea's comparatively smaller "assets".
Though Chelsea could be plotting Elma's horrible demise right now as we speak. After all, when she's being loud and obnoxious, then you might be able to work it out with her; but when Chelsea's being quiet, that's when you know you got a serious problem on your hands. ^_^;
Anyway, enjoy! =3
Elma copyright Dragonman32 Chelsea and artwork copyright SatsumaLord