korean lyrics in video:

You can lean on me now, I’ll always be next to you
Because you gave me everything
Because you were my support
You can believe/rely on your son now, you can smile now
I finally know the heights of your kindness
You became my blood & my flesh
Remember, mom?

— 「 claire ⁷ 」 (@btstranslation7) May 12, 2019