Hello,
Thanks for posting your query.
Purplish lumps on inner thighs could be either a sebaceous cyst or a infected hair follicle or a fungal infection.
However considering the size, location and the seeping nature of the lesion it seems most probably to be a sebaceous cyst.
A sebaceous cyst is a lump that is found on the body. It contains a closed sac that contains an oily substance that resembles cheese. This substance is called sebum. Often the contents of a sebaceous cyst have a foul odor.
An experienced medical professional can usually tell what it is by a thorough physical examination of the lump . However, doctors sometimes order biopsies in order to make sure a patient doesn't have another condition that looks similar. Treatment is usually easy as well. In fact, most sebaceous cysts don't require any specefic treatment unless it is infected .
Though most sebaceous cysts do not develop into anything different, it is possible for them to get infected and form abscesses. When this occurs, the patient may experience pain in the area, and removal may be necessary surgically .
Meanwhile you can try the following for some relief,
1.Apply moist heat to it. You can either use a moist heating pad or take a washcloth and wet it with extremely hot water. Place it over the cyst for about 15 minutes two times a day.Take care to wipe the region dry later to prevent moisture induced fungal infections
2.You may try prescription antibiotic ointments like mupirocin if there is any pus oozing out or pain or redness or increased warmth and swelling in the region.
3. In case there are any more such lumps or there is progressive worsening of the present lump it's best to consult your dermatologist who can confirm the diagnosis and start appropriate treatment .

Hope I have answered your query.
I'll be available for any follow up queries.
Regards

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