What causes a visibly risen (5mm), hard, white, rounded, non movable lump on your bum? It s about an inch down the crack and it very pressurized achey pain when my cheeks touch. I have high hygiene standards and use perfume free soap, but it looks like a massive pus filled dot, but when I tried to gently squeeze it with a hot cloth it wept a little bit of very thin bloody liquid, but stayed hard. It is very painful whenever it touches anything and feels under pressure.