A 24 year-old man needs the helping hand of his ex-rival?s foul-mouthed womanizing ghost to overcome his impotence and get laid.

“A 24 year-old man”

This line doesn’t tell us about the main character. You should say something like: A lonely librarian, an uptight business man, A reclusive neat-freak.
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“ex-rival?s foul-mouthed womanizing ghost”

This should be changed because it’s a little confusing. (It could be read that his ex-rival had the same ghost haunting him)

“The ghost of his rival, a foul mouthed womanizer,”
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ex-rival

There is no context for this, was he a rival at work? Was he a rival for the love of a specific woman?
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“needs the helping hand” “to overcome his impotence”

Is his rival giving him handjobs??? If so, this is a great line, if not, I would change the line to avoid confusion 🙂
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Interesting premise for a raunchy comedy, good luck with this!