On December 19, Sulli shared a photo from a premiere event for the new film 'Master', where she posed with actor Lee Sung Min (48) and model Bae Jung Nam. The controversy arose from her captions to the photo which read, "Meeting for the first time in awhile with Sung Min-ssi whom I love, and Bae Jung Nam oppa. Let's all go cheer on Dong Won oppa!"

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Netizens' issue is that Sulli called Lee Sung Min by only his first name while adding "ssi" to the end. They argued that while "ssi" is a form of an honorific suffix used to express respect, it was inappropriate to use the suffix toward someone several years older than Sulli.

In response to the criticism, Sulli left a comment under her post, saying, "It's just a nickname that I use. Don't react so sensitively! Haha."

Meanwhile, netizens are continuing to criticize Sulli, claiming that her choice of words was rude. Comments said, "Sulli really did wrong this time. No matter how close you are, using a nickname like that is rude to both Lee Sung Min and his wife..", "She calls her sunbaenims who are way older than her 'ssi.' What did she do with her manners?" etc. 

What are your thoughts on the matter?

???? ?? ???? ???? ??? ??? ?????? ?? ????? ????!!!! #??? ??

A photo posted by ?????? (@jelly_jilli) on Dec 19, 2016 at 3:58am PST