Choosing between master's in English literature or political science depends upon what are your future career goals. Let me elaborate both for you:

Political science : it mainly focuses on governance, political theory, international relation, public policy etc. Here you can have career opportunities in government, NGOs, international organizations, academia and political consulting. You can develop your analytical skills.

English literature: it mainly focuses on critical theory, literary analysis ,  cultural studies and writing. Here you can have career opportunities in writing, publishing, education, journalism and research .  Your communication skills and creativity will be enhanced.

I think these points will surely make your decision much more easier. Good luck.