Kim Soo Hyun’s love letter to 17-year-old Kim Sae Ron unearthed: ‘I love you Saeron’

Kim Soo Hyun’s letter to Kim Sae Ron

On March 12, 2025, Garosero Research Institute (the YouTube channel that first exposed their connection) revealed a handwritten letter Kim Soo Hyun sent to Sae Ron while serving in the military. At the time, Soo Hyun was 30 years old, and Sae Ron was just 17.

Dated June 9, 2018, the letter shows Soo Hyun calling her “Saero-Nero” (Kim Sae Ron’s nickname). He described his day in vivid detail, from unpredictable weather and karaoke sessions to sunbathing on a helipad. He mentioned watching Heart Signal 2 and spoke about the changing seasons during his training.

A part of the letter (via Qoo) reads, “Today, the weather was so unpredictable that I felt like I was being tossed around in all directions this wonderful Saturday. What a great day for writing something and thinking about you, Saero-Nero.”

Also read: BTS gets dragged into Kim Soo Hyun’s dating controversy

But beyond the casual storytelling, the tone of his writing turned more emotional. He then wrote about missing her and wanting to share the simple things that brought him joy. He said, “I want to share what I find beautiful and meaningful… even if it’s hard to see your face, I still want to tell you how I feel.” Toward the end of the letter, he added, “Please take good care of me” (a phrase often used in Korea when asking for someone’s support or understanding).

He continued, “What I’m trying to say is… I just want to share what I think is good, what I find as joy, what I’m looking at or feeling… I want to share these things with you. It’s hard to see your face, but I still want to share with you how I feel inside. What I’m willing. I don’t want to burden you… So, I guess what I can say is… I miss you.”

The letter seems to have made things worse for the K-drama star because of the timeline and their age gap. Reports claim the two were in a secret relationship for six years, something that had long been rumoured but not confirmed until now. 

Kim Soo Hyun’s old military photos with Kim Sae Ron 

On the other hand, old photos from Soo Hyun’s military service recently resurfaced. One shows him kissing Sae Ron, while another postcard, dated January 1, 2019, reads, “I love you, Sae Ron.” The photo card allegedly sent from Paris also mentioned being drunk in that message.

Both Kim Soo Hyun and Kim Sae Ron kept their relationship out of the spotlight for years. Sae Ron, known for The Man From Nowhere, focused on her career, while Soo Hyun, who rose to fame in Moon Embracing the Sun and My Love from the Star, kept his private life quiet.

I’m so invested in this Kim Soo Hyun- late Kim Sae Ron issue. This pedo is a criminal pic.twitter.com/N6msdDzVFt

— vee🤍 (@queenjenruby) March 12, 2025

Damning Photos Kim Soo Hyun Sent To Kim Sae Ron 7+ Years Ago Exposed pic.twitter.com/gYBFnzTIDn

— minjeong (@minjeongyarrrr) March 12, 2025