It really -doesn't- make sense. At all.

I couldn't care less, to be honest. Never was a fan of Lightning or XIII in general, but I played them because it's Final Fantasy.

From a physics standpoint, yeah. Boobies jiggle. But in -what- Final Fantasy game have you played in which a female character's did this? 7? 10? Tifa and Lulu are the only other "modern FF" female leads to have bigger chests and their's don't jiggle.

I take that back. Apparently they do in Dissidia 012. Or at least that's what I just read anyway.

There went my argument.

Lightning magically enhanced them. There ya go. There's the explanation.