Let her get a £10 cake at Morrisons, it won't look anything like that. If she's lucky it will be a sheet cake with some monkey iced corset shape on there, and she can spend all night explaining what it's supposed to be. Her friends will ask her why she didn't come to you for a cake, and she'll have to say she didn't want to spend the money.
What kind of business is she in?
(I'm not going to go into whether this is really an appropriate cake for a mother to get for her 18 year old daughter !)
Glad to see I wasn't the only one thinking that cake is a little out there for a just-turned-18-year-old. Especially with the whip: makes you think of S&M. Yeesh!