Don't shave is even better, shaving causes tiny nicks on the skin predisposing one to ingrown hairs and staph infections which cause boils.
I had some luck recently treating my grandson's boil with thyme tincture and a salve my friend made; the ingredients of the salve were myrrh, frankincense, calendula, beeswax, and olive oil. The boil was cleansed with the tincture and then the salve was put on it, within a few days the boil came to a head and then began to drain. Treatment is being continued until it is completely resolved as it almost is.
Keep it covered with gauze and note that boils are contagious.
I am sure you can find some similar salve or ointment online and the same with thyme tincture. I don't know how she made the salve but the tincture I made by chopping fresh thyme, enough to fill a quart jar and then covering that with as high a proof alcohol you can find: everclear or vodka. Shake it and let it sit in a dark cool place for two to three weeks and shake it now and again. Then pour it through a sieve into clean bottles and store in a dark place. I find thyme tincture to be useful for a number of complaints.
There is also a Bartholin's Gland in the perineal area that sometimes gets infected.
Good luck.
Try using an antibacterial soap like Dial
If your bikini line looks bumpy and red after shaving, you may have ingrown hairs. Ingrown hairs happen after the hair is shaved, says the Mayo Clinic. When the stubble grows back in, it may curl, growing back underneath the skin and causing an irritated bump. Consult your doctor about your ingrown hairs, and if he approves, you can use home remedies to treat them.
Washcloth Rub
Prep your vaginal area for shaving by gently rubbing the skin with a washcloth, recommends the Mayo Clinic. To help soften ingrown hairs and get them to stand up straight, wet a washcloth with warm water. Using a circular motion, rub the skin you are about to shave for several minutes. Before bed, repeat the process again for several minutes. Continually rubbing the area before shaving and before bed with a washcloth will ensure the hairs grow straight and that they do not grow back underneath the skin's surface.
Needle
To remove ingrown hairs that have already lodged themselves underneath the skin, the Mayo Clinic suggests using a sterilized needle to carefully pull out the hair loops. Sterilize the needle by placing it in a glass of rubbing alcohol or hydrogen peroxide for several minutes. Dry the needle completely with a clean paper towel. If necessary, hold a magnifying glass or magnifying mirror in front of the skin to see the area more easily. Carefully slide the needle underneath the hair loop, then pull upward to remove the hair from the skin.