I'm surprised she doesn't already have one actually. It seems right up her alley. I'd imagine her scent and the bottle being like most people have already said: cute shape, A symbol, and sweet, floral scent. The only celeb perfume I've bought is Curious for no other reason than it's part of Britney's line lol because I'm really not a perfume person. Luckily the scent suited me just fine and I loved it.

I've been kind of interested in Gwen's Harajuku Lovers line (because of the adorable packaging) I haven't had the chance to sample any of it yet though.
But yeah, I'd totally buy Ayu's line because I'm sure the packaging would be super cute and girly.