I just read about this free software and it's no different then the one that is already on your PC, under Windows Administrative tools, one exception is that this is an executable tool that you can put on a flash drive take with you if you use a public or unfamiliar computer to remove traces of your activity.

Is this the same "DiskClean" written about in this Malwarebytes article?

https://forums.malwarebytes.com/topic/60979-removal-instructions-for-diskclean/

It's unnecessary, in my opinion.

DiskClean Main --> DiskClean.exe Added by the DiskClean Korean ROGUE! anti-spyware program. Note: Located in \%Program Files%\DiskClean\

Reference from here

http://www.systemlookup.com/search.php?type=filename&search=Diskclean.exe&s=