In You Who Came From the Stars, episode 18, Cheon Song Yi(played by Jun Ji Hyun) found out that Do Min Joon(played by Kim Soo Hyun) was going to die. Song Yi and Min Joon was on the way home after a date. Then Min Joon got a call and said to her, “Go into our house first. I’ll be right back.” Song Yi was excited that he said, “Our house,” and happily went in. At Min Joon’s house, Song Yi found his diary and started to read. She started off reading with a smile, but soon she started to tear up. In the diary, he wrote, ‘If I miss the chance to return to my planet this time, I might disappear in this world. I probably would end up dead…’ Song Yi realized that Min Joon might die if he does not go back to where he came from, and burst into tears.