He says he found someone else.

Someone who can fill that empty spot in his heart. He was only watched from the shadows, yet he was able to make him smile, something Jongup and only Jongup could do. Of course, his first reaction was to be happy for his friend but soon after, he began to feel a little lonely himself.

But wasn't Himchan his best friend in life?

Why did he feel so insecure about their friendship?

Jongup feels like he's fading away, slowly being forgotten.