Eunwoo was your enemy since highschool, but he secretly liked you. You and your boyfriend were having a heated argument and he threw your favourite necklace to the river. You started crying because it was your favourite necklace. You didn't know Eunwoo was there and saw the whole scene. Eunwoo grabbed your boyfriend and threw him to the river.

Eunwoo: "Now go look for it." he said in a stern and angry look