<s>[INST] I have a hard lump on the back of my neck with a small black dot hole. .it kind of looks like a black head but it has a tiny open hole ..And when you squeeze it a string of dark smelly pus just keeps coming out. But it gets to a point where I can t squeeze without breaking skin but the pus is still coming out. And it never bleeds I normally stop to keep from bruising my skin. [/INST] Hi,From history it strongly suggesting of infected Sebaceous cyst giving this lump.It might require excision of cyst with sac.Consult surgeon and get examined.Ok and take care. </s>