I am having a hard time finding a budget airline that goes from seoul, korea into any one of the Southeast Asian countries. does anyone know of an asia pass that includes south korea or a budget airline that goes out of seoul to any country in southeast asia?
Jin Air was supposed to start Seoul-Bangkok service - I don't know if this ever actually happened or not. Korean Air's Air Korea was also mentioned in the press. Sorry, I don't have much more than this info. You might have to ferry to China and catch an Air Asia flight.
Jin Air does have a home page. It lists BKK as one its destinations. Good luck.
CebuPacific is the low budget carrier from th Philippines that flies from Incheon Airport.