Yep. Or you can say, Their butt's close to the sidewalk, they're stalky, they never really hit their growth spurt, they're on the taller side of short, they're knee high to a grasshopper, etc.
a flaky person is like, someone that can either be EITHER OF THE FOLLOWING:
-annoying
-crazy
-bizarre
-wacky
-odd
-or literally flaky with dry skin or dandruff or something.
Calling...