On the June 22 episode of 'Radio Star,' SISTAR's Hyorin mentioned what the most difficult part about the 'diss battles' on 'Unpretty Rapstar' was.�

The idol revealed, "It's not that I wasn't cool about it but it was difficult to go up on stage and diss Yubin without my feelings getting in the way."�

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Hyorin continued, "I kept a one-track mind and thought that I should just do [the diss]. But I was angered the moment I heard [SISTAR] members' names; when I did the [diss battle] with Yubin, I was wondering why the members' names came up. So I told her not to say anything about her platonic love for J.Y. Park."�