He posted a letter reading, 

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"Hello! This is F.CUZ's leader Jinon.
Lately, it's especially important to take care of your health because of the dust and the difference between night and day. Be careful not to catch a cold in the changing weather. The cherry blossoms have blossomed so beautifully recently. Have you gone to see them? When they've fallen, I think it'll be a warm spring with the perfect temperature to go on a walk to somewhere close.
In this great weather, I'll be enlisting, like any Korean man has to in his lifetime. I'll be enlisting to the training center in Gangwondo on May 8. I've been preparing myself, but I wondered how to tell you when I suddenly got the summons, so I've decided to write this letter.
As I promoted for over 8 years, I've made so many good memories and received so much positive energy, so I think I'll be able to do well in the army. I'll come back healthily! Thank you always, and I love you so much. And my dongsaengs in F.CUZ! I ask for your unchanging love and support. Thank you.
Thank you, For U."

Will you miss him while he's gone?