$ sudo apt-get remove buffy 

Uninstall buffy including dependent package

If you would like to remove buffy and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove buffy 

Use Purging buffy

If you use with purge options to buffy package all the configuration and dependent packages will be removed.

$ sudo apt-get purge buffy 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove buffy 

See Also,