Munja 5 - Galbijim

나를 슬프게 하지 말아요...당신의 마음속엔 내가 없나요? 당신에게 나는 어떤 존재인가요...?

Please don't make me sad...is there no room in your heart for me? What am I to you...?

슬프다 - to be sad. 슬프게 하다 - to make someone sad.
하다 - do 하지 말아요 - please don't
당신 의 - your
마음 - heart
속 - inside
엔 - contraction of 에는. 마음속엔 means 'as for the inside of your heart'.
없나요? - this 나? or 나요? is a way of making a sentence into a question.
에게 - to. 당신에게 means 'to you' or 'for you'. 에게 is for living things, whereas were it a nonliving object it would just be 에.
어떤 - what kind of
존재 - existence
인가요? - is / am what? 은가 or 는가 is another way of making of question.

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