Thanks for contributing to the pear point of view!
I believe it IS necessary to work a muscle in order to tighten it, and yes - the right type of exercise will even decrease the size of it if you are not currently working it out - as fat will develop intramuscularly as well as under your skin (think of a steak being marbled with fat, compared to a lean piece of meat), but your point in not working the muscle to the point of making it grow a lot is correct.

It's a tricky situation. Hit it too hard and it will get bigger, leave it alone and it will be soft and flabby. However, nutrition is a contributing factor as well. When you're at a caloric deficit, you get smaller. At a caloric surplus, your muscles get bigger. I'm getting stronger right now, but everything is shrinking.

I think lot of people fall in the "in between" catoegory though, and while they may feel like their butt is huge, it's not actually, genetically, the type of bum that's size and shape will benefit from not working it out.

Another thing - having shapely legs WILL improve the overall appearance of your lower body, no matter how large or small your rear is. Mine always looks better when my hamstrings are properly and propotionately developed. And when my quads are larger, the butt/hip area appears smaller. So even if you're trying to avoid getting bigger in your rear because you're truly one of those people who have a butt that just grows like crazy - don't avoid lower body exercise...even if you decide to stay away from the heavy squats and weighted lunges.

When your bodyfat is lower, body shape tends to even out and look better, even when you have a bodypart which may be disproportionate - like a large waist, or a large rear. It just looks better with less fat on it. Fat exaggerates everything, especially the things you don't want it to.