Su-ji and U-ri

A Clue To Track Down Yoon-ja (1x51)

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In her haste to escape, Yoon-ja abandoned her jacket, which Sun-young later discovered, uncovering a lead to locate her. Yoon-ja is haunted by regret over her actions toward Sun-young, actions she wishes she could undo. Meanwhile, Do-young stealthily tails Jang-soo, who claimed he was off to play at an early-morning soccer club, only to stumble upon the disheartening truth. Ma-ri comes across Sun-young and Jin-tae in his office together.