HELP! My daughter wants to dress "ual" for halloween, How do I handle this?

HELP! my daught mist told me yesterday that she would like to dress very "ual" for hallows ween this year you know? she is a 17 year old teen aged girl and I do not know if "ual" tires are approp for her you know? she perused the local hallows ween shop with her pal mandy and came home with a very inapprop and revelead foot un form ok? This costume set included a large hard helmet in the shape of a very inapprop male bodily functioning part, also included was, an upper attire padded numerical top stating very ual and inapprop numbs and a pair of very very tight and seductive padded crouched pants. Mist then decided to wear her high heeled tennis sneak shoes. she is also going to be carring a very explicit and inappropriately shaped "football" style waist pocket purse.. what can i do? should i let her wear a revealed costume? is it inapprop? you know?