Responses
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I'm not even sure which person in this thread to reply to lmao
My answer personally would be that it's kind of in between. They don't float to the top of the water like in anime, but they do float up a bit! Not sure if size and weight of them varies how much they float? (If so my answer would be based off my natural G cups, lol).
The only science-y thing I do know about boobs is that they all have the same amount of nerve endings - so they're more spread out the bigger the boobs, thus you feel less. Hence my original comment ٩(๑❛ᴗ❛๑)۶
As someone with boobs that big, I relate to Shion's complete lack of reaction to the boob slap. Your boobs get that big and you feel next to nothing from that - pain OR pleasure (or a mix if you're into that, lol).