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Rain surprised fans on his Instagram on October 8, revealing, "A special guest is appearing today...appearance by So Yool's father. keke. Please look forward to it." The singer-actor also shared a�friendly snapshot of the two holding the script for the SBS Wed-Thurs drama.

Even for those who don't watch the drama, it was still a pleasure to see the former JYP Entertainment�labelmates reunite to show their support for each other.

Stay tuned for this cameo!