SEE ALSO: Teacher will have you giggling and wowing at his dance cover of 'Me Gustas Tu'!

The teacher, named Joo Jin Seok, revealed that he is a big fan of Yerin, telling her, "It's an honor to meet you." I'm sure Yerin was honored as well to meet such a dedicated fan of hers! She mused, "From the way he did his hair, I knew it was me. Even the curls are exactly the same," bringing laughter. 

Joo Jin Seok then went on the put on a performance of "Me Gustas Tu" with G-Friend, taking over Yerin's parts and imitating every one of her moves down to the facial expressions! 

Umji praised the teacher to no end, saying, "There is an special bright expressions that Yerin makes. I was shocked that he had on the same exact expression as Yerin. He's awesome." And we have to agree. Just make him a permanent member already!