bump now rash

I am concerned about my boyfriends rash.  About a week ago I noticed a bump in on his buttock, at first it seemed to be simply an ingrown hair.  We left the bump alone, but last night we noticed a red splotchy rash has appeared as well.  The rash is not touching nor seems to be originating from the original bump.  

The bump is a pink color now, but was toned to his flesh a week ago.  Originaly the bump was not sensitive to touch, but now has become sore but does not itch; although the change in color and sensitivity may be from his awareness and habit to touch and pick.
The rash is located at the bottom of both buttocks, but do not run into eachother.  The skin is smooth and level, no blisters or scales.  I would have to describe the color as a deep red-burgandy, similar to a red wine.  He says it does not itch.

After reading other posts online I believe the bump may be Molluscum Contagiosum, CA-MRSA or HA-MRSA, but in everything I have read so far, I have not seen any cases were a rash formed in the following days.  Any help as to what this could be would be greaty appreciated.

[Bhupinder Kaur, MD]

Hello,
From the symptoms it can be a boil. Boil on buttocks is usually due to plugged sweat glands that become infected or by an ingrown hair.

Apply warm compresses on the boil and keep the area clean. Drainage of the boil is done only when it becomes soft and forms a head. Take some over the counter pain reliever and consult a doctor for examination and antibiotics prescription. If there are recurrent boils, then please get your blood sugar levels estimated.

It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.