Just a day before, IU revealed that actress Tang Wei had sent her a heartfelt handwritten letter expressing her affection and admiration.

After appearing in IU's "Shh" music video, Tang Wei and IU were able to form a special relationship. In Tang Wei's heartfelt letter, the actress shared, "There were two touching moments that I wanted to share with you. During the filming, the director directed me and told me the lyrics 'My eyes that are just like her mom's' that you wrote. I felt a resonance in my heart at that moment. It was something I had never thought about before."

Then, on February 23, it was revealed that IU had also sent a letter to Tang Wei.

Tang Wei shared the letter on her social media with the caption, "I remember that Korea was particularly cold on the day we took the MV, but I received the warm sweater, heart-warming card from you, and stomach-warming chocolate."

IU wrote the letter in English and Korean: "Dear Tang Wei Sunbaenim, Thank you for being a woman like an impossible riddle who cannot be easily standardized because of its complicated beauty. It is an honor working with you. I picked a gift that might suit you. I hope you stay warm and healthy. I'll always be fond of you. "