No one can be good forever, and no flower can be red forever!

Aaron Zhao slapped his sister-in-law Amelia Li on the butt without any hesitation, then walked away whistling.
Amelia Li was so angry that she pouted and stamped her feet, saying, "Humph! I told you to hit me, but you really hit me."
As soon as she finished speaking, Olivia Li opened the door and saw her sister in the corridor, while Aaron Zhao was walking away. She frowned and asked, "Little sister, what are you doing here?"
Amelia Li stuck out her tongue, said "nothing", and slipped...