Views.

Screenshot of Zhijing's comment.

1. Daniel can be polite, just that you don't know.
 Or he feels that there isn't a need to be polite to you.
Furthermore, Kangjie is his friend. So he's polite to him.
*view picture* (defination of "polite")

2.Kangjie posted it on the class page,
thus Daniel CAN report the picture if he wants to.
And this is Iphone/Ipod version of facebook message's inbox.
*view picture.* ("Ipod" on the top for proof.)
PS:it's just some random message people sent to me.

3.It can be reported even if the picture is w/o any obscenities.
*View picture*
PS:The picture in the background is none other than
zhijing's profile picture.