ignore the ignorance dude.  there are courses available to foreign students at just about any of the universities.  not only that, admissions to foreign students are much easier than for korean students, in terms of academic qualifications.  trouble is, all the courses are taught in korean, except for english that is, so you would need to be somewhat fluent in the language.  secondly, if you're trying to earn a degree in order to become an english teacher, most schools look for degrees from overseas.  for example, one of the requisites for an E2 is is that your degree must be from an accredited university from an english speaking nation.  but with an F2 it may not be much of an issue.  i am also an F2 but as my degree is not from korea i would not be able to tell you. 

what i would do is check in with PNU.  just walk into the registrar or something and ask.  that is the biggest university in korea's second largest city and i'm sure there are foreign exchange students there.  i know in seoul, the universities have actual foreign student departments but not sure about down in busan. 

well...hope that sheds a bit of light.