One Act of Nothing and Everything.

It's Yoon Ji Hoo messing Geum Jan Di's hair in Boys Over Flowers (KBS had a marathon of the episodes last night and I caught that part).
It's the young boy Kim Dong-young patting the young girl Kang Hee's head in Fashion 70's. A moment that will be replayed again and again as she went through life.

It's scenes like these that remind me of you, of that time when I got a new haircut and you reached out to place some strands behind my right ear. Little thing. Major shock.

The boy in the drama, like you did, just smiled and went on. While the girl is unable to move, suffering inside. The best she could do is smile like crazy when the boy is no longer around.

It's like a silent firework has shot through the skies.
It doesn't announce itself with a bang but humbly inspires with its burst of lights and colors.
As are fireworks, it's a one-time thing, one special time enough to make lasting impressions.