C92 What Lipstick Print？！

Xia Anran's gaze slowly swept across Gu Zichen's body. She suddenly noticed that his collar was open. Although it was only a button, it didn't fit Gu Zichen's strict style of dressing at all.

Xia Anran narrowed her eyes to take a closer look and discovered that there were still some red marks on the inside of his collar. When these two strange details were combined