Backstage at 'M! Countdown' on the 25th, Krystal revealed what her first love felt like and shared, "It's a heart-fluttering feeling," while Luna added, "Sparks fly." On the other hand, Victoria shared that a first love is not always such a happy thing, "It hurts a little at first, but once that phase passes, you feel all right."

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Although Sulli previously mentioned that she once fell for one of her bodyguards, it seems that wasn't enough to be considered her first love as she confessed, "I've never had a first love. It will come someday I hope?" 

Though Sulli hoped that her first love would come one day, Amber seemed indifferent about it. She shared, "To be honest, I don't care so much about my first love, so I don't really know what to say."

f(x) will continue their comeback stages with "Rum Pum Pum Pum" this weekend and release 'Pink Tape' on the 29th!