If your proposed company name contains words of a sensitive or explicit nature, the company name will not be approved by Companies House without a supporting justification for the use of such words.
Sensitive words are words which:
A complete list of sensitive words, and what you will have to prove in order to have permission to use a sensitive word in the name of your company can be found at Companies House web site.
In order to use a sensitive word in the name of your company, you must supply supporting evidence to Companies House when you apply to have your company incorporated.