I'm 45 years old... I've had cyst type issues in the pube area for over 10 years... it started with one and over the past 10 years it's turned into a reoccurring and painful issue.. after a decade of suffering I finally figured out what is happening and how to avoid and treat this...
if there is puss and pain and swelling.., it could be a cyst a boil or abscess... regardless... the one thing they all have in common is Staph... puss equals staph.. if your cyst/abcess/boil hasn't come to head... go to Walgreens and buy some Prid (drawing salve) clean/soak in a hot tub before bed... apply the Prid and you should see it come to head overnight... if it's already come to head... it needs to drain... I take a soft dish towel and cut it into 4.... I wear boy short panties during and fold the soft towel and place over the area and change it out several times over the day... heat in that area only increases staph... keep it dry and let it drain.... next... wash the area daily with hibiclense (also available at Walgreens but cheaper on Amazon) get the foam pump, as it doesn't self foam....and will last longer with the pump... wash thoroughly and then wash with the hibiclense... and let sit on skin for 3 minutes before rinsing.. this soap kills staph and lasts for 24 hours... once you've cleared up the infection... use the soap at least once a week but try to use it twice... once the cyst/boil/abscess is reoccurring you have to be diligent in killing the staph... especially in the summer when it's hot and sometimes sweaty down there...
after 10 years of painful puss filled and embarrassing discomfort, I can attest that THIS works.
Antibacterial soap but it should be unscented or exfoliate with salt texture exfoliant.
If you're shaving, make sure you're shaving correctly, the "bruise" you're seeing is most likely an ingrown hair that's growing under your skin. Whether you remove the hair or it breaks surface it's self, it will be long! But after the ingrown hair is exposed and plucked out, the bump will go away. Antibacterial ointment can be helpful as well. Don't pick at it too much because it will spread.