When they were 15 years old, they were close friends
When they were 17 years old, they were soulmates pursuing each other
At the age of 24, they were the closest strangers
"The meaning is hard to find, which has two meanings. One is that you can't find it when you ask for it, and you can't find it anywhere. But the other is that this thing is precious, so it is hard to find."
Purpose: redemption