Little more about the risk.
Hello sir and welcome.
Need some more detail:
What exact you mean by a risky exposure? Was she HIV
pos/Commercial sex worker?
Was it unprotected?
All the blackening, rashes and the cuts which are there in picture were all due to fungal infection
. Apply any antifungal powder and keep the area dry. Improve your genital hygiene. Change underwears frequently. You will be alright for that.
Hope to listen from you soon.
My best wishes and prayers are with you, live healthy and happy.