My company used to do them (we no longer do any adult-oriented work) so here's some free advice when looking for the right contractor(s):
1) Descriptions must be kinetic. There must be motion or action in the description. The action did not happen in the past. It isn't about to happen in the future. It is happening NOW!
Solution: Think and write like you're writing your resume. Focus on verbs. Actually, focus on the RIGHT verbs.
2) Choosing the right words. While long dry and semi-technical words convey the same technical meaning as shorter slang words, they don't have the same effect. Avoid them. Use short, choppy, easy to read (and thus highly effective) words that have an EMOTIONAL impact.
Words are NOT neutral. There's a world of difference between then. They come from differing contexts. They appeal to differing emotions and situations. For adult, you are looking for words that connote IMMEDIACY, exoticism, or otherwise an extraordinary event.
3) To be continued at
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