"Why do you live?" asked Sehun.
"To love you." answered Luhan.

"Why do we live?" asked Sehun.
"To love each other." answered Luhan.

"Why do I live?" asked Sehun.
"To love me." answered Luhan.

Everything is meaningless.

Sehun killed himself,
and left Luhan.

He probably didn't love him enough, that's what Luhan thinks. Loving Luhan wasn't enough to live.

Luhan understands that.

Because he doesn't love Sehun enough either to join him. Loving Sehun isn't enough to die.

Or maybe Luhan punishes himself by living without Sehun.

Till death do us part.