As introduced in the previous post, in Korean, "to follow" is 팔로우 하다 [pal-lo-u ha-da]. When you want to say "to follow back", however, you need to use a completely different word.
This is in fact a combination and abbreviation of two words: 맞 + 팔로우.
맞 [mat] here means "facing", "directly opposite", or "each other", and people use the term "맞팔" for "follow back" and 맞팔 하다 in the verb form.
맞팔 [mat-pal] = follow back, following each other
맞팔 하다 [mat-pal ha-da] = to follow back, to follow each other
So when you follow someone and the other person follows you back, and you want to say "Thanks for the follow back!" you can say:
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