It is about a forbidden love story between a teacher, Bae Joohyun, and a senior highschool student, Huang Renjun. 

Bae Joohyun or well known as Irene, the leader of Red Velvet, is a very shy and the most awkward person alive. She doesn't really like to talk to strangers. Not that she doesn't want to but she can't. Her mind wants to approach others first but her body doesn't allow her to. She is actually a very warm and caring person, but her image makes her looks so hard to approach.  Kim Taehyung

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