ayu´s lips bigger this year you have to recognize

[jbrat2219]

I'd say just make up and aging. And of course, lip plumper.

I'm not one of those people who think Ayu would never get collagen but I think the reasons I listed are more likely considering the several pictures of her without make up recently show her natural self and I don't see any signs of collagen, not that I'd know what they look like to be honest xD;