This song a drama OST theme, is extremely popular in South Korea. I only discovered it lately, because I haven't watched the drama. I think the lyrics and melody are beautiful. I'm hoping that somehow I can get the video posted. This is Younha singing the song Kim Yuna wrote and arranged. (I had to edit this because of the name confusion; Jaurim is a group that Kim Yuna performed with as lead singer on the original). The official English translation of the title is Goodbye Grief.

스물다섯, 스물하나 Kim Yuna: lyrics and melody, Jaurim: orig performance

In that season when flower petals blow in the wind
Still, holding your hand comes to mind.
Now as then, those beautiful flowers
I couldn't consider them wistfully as I do now
Oh, your fragrance carries on the wind.
Oh, I thought they'd last forever, twenty five, twenty one.

That day the sea, was so warm.
Still, holding your hand comes to mind.
In the breaking sunlight, you and I
Our hearts racing in a joyful dream.
Oh, that day, the wind carried a song.
Oh, I thought they'd last forever, bygone days of you and I.

Your voice too, your very eyes
Even your affection and warmth
As I remember, goes far away,
dissipating not to be embraced again.

In that season when flower petals blow in the wind
Still, holding your hand comes to mind.
Now as then, those beautiful flowers
I couldn't consider them wistfully as I do now

Oh, your fragrance carries on the wind.
Oh, I thought we'd be forever twenty five, twenty one.
Oh, that day, the wind carried a song.
Oh, I thought they'd last forever, bygone days of you and I.
Oooo ooh...
Oh, I thought we'd be forever twenty five, twenty one.
Oooo ooh...twenty five, twenty one.

Hangul Source: Musixmatch