It looks to be a cyst
. Cyst emits out thick pus like or other colored fluid out of the punctum ( hole). Sebaceous cyst is common at the end of the penile shaft or the scrotum
. It is most often foul smelling fluid.
It is formed by the collection of the inner lining of the cyst. THe cyst is actually enlargement of the sebaceous gland
a modified sweat gland
. It is not worrisome.
It can be excised or the fluid can be expelled. Please see a doctor for the same.