You can buy depilatory that is made for intimate areas but you still can’t put it on the vagina or the butthole. It burns.
I am so sorry, you are going to be miserable for a few days. Lotions and balms are probably going to make it sting even worse.
I think one of the Pixels or one of the old nexus devices could read heart rate through the camera somehow, but you had to put a big fingerprint on the lense so it was useless to most people.