Hello!

I always want know if the other read my PMs.

This is my idea.

What do you think?

that's already possible with read receipt.
https://gyazo.com/bbdb8024e91cb75f84f0a770a3228fc0
then you go to this page
http://forum.toribash.com/private.php?do=trackpm
and see if they've read it

Thanks!