Fanfics are a part of the kpop package. Nobody can deny they haven't read fanfiction, it goes with the territory. But, what is funny/embarrassing is when Idols read them and they react to it.
Heechul posted his own fanfic on instagram about HeeTeuk
He also wrote a EunSiHae fanfic.. Check it out here https://www.asianfanfics.com/story/view/572931/translation-of-eunsihae-fan-fiction-written-by-kim-heechul-donghae-eunhae-eunhyuk-sihae-siwon-superjunior-eunsihae
Yesung horrified when he read a YeWook fanfic
Zico once said to his fans, "Can you only write this much?" OoO
SS501's 4D leader wrote a fanfic about him and his member. Jung Min was horrified because he was portrayed as a sasaeng. Check it out here http://kathysbench.blogspot.de/2011/03/his-and-her-letters-fanfic-written-by.html?m=1