yeah, if you are FAT, not if you gain a little bit of weight. and she clearly isnt fat
Dude, any weight gain, or loss, also shows itself in a women's breasts, just like any other part of the body that has fat deposits. Regardless of the starting body type, if you gain weight there's a chance a women's breasts will get bigger. Just like as a women loses weight and gets leaner, their breast size will likely also get smaller. Even if the change is just 5 or 10 pounds. That weight has to go
somewhere
Plus, haven't you heard someone claim that fat goes to their legs/ass/stomach? If someone gains weight and their boobs get bigger, then you talk about how their shirt is bursting at the seams because of their breasts, it's not crazy for that person to be offended by it because you're pointing out the result of them gaining weight. Even if you as the person pointing it out doesn't mean it that way, it can still be interpreted that way.