Brief Answer:
It would be on the genital area unless you spread it

Detailed Answer:
Hello,

Both herpes and syphilis first appear on the site of inoculation which is the mucosa of your genitalia (if it happened!). Syphilis usually appears as an ulcer 21 days after transmission.
Herpes usually appears much faster (in a few days) but it may also be asymptomatic (no appearance).
Generalized herpes is very unlikely and almost exclusively occurs in immunocompromised individuals.
Generalized syphilis may happen if left untreated without further inoculation in different areas.

I hope I've helped!

Kind Regards!

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Brief Answer:
I'll be more explicit this time

Detailed Answer:
Hi,

the herpes virus invades nerves. The virus lies dormant in a very specific nerve that is has invaded and may cause exacerbation from time to time. The visible lesions are supposed to extend only to the part of the skin or mucosa that's innervated by the specific nerve. Generalized herpes means that other nerves have been invaded too and may occur when the host's immune system is defective. So the answer is that lesions are expected only in your genital area, unless herpes has also been inoculated to your lips or throat etc

Syphilis won't remain as dormant as herpes. It continues to spread and may affect other parts of the body causing generalized skin lesions or even neurological problems (after being left untreated usually for years).
Particularly in syphilis, we expect a very specific lesion to appear (an ulcer) in 21 days (most of the times) in the area of inoculation. No other area can be affected at this time.

I hope it's more clear this time!
Contact me again, if you'd like more clarifications.

Kind Regards!

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