A plugin that lets you quickly and easily create new plugins.
Nope, not in the slightest. You have been warned.
That said, it's perfectly "safe", given a certain defintion of the word "safe". The "create a new plugin" screen itself is secure, and inaccessible to anybody who lacks the capability to "edit_plugins" to begin with. Pluginception also uses the proper WP_Filesystem methods to create the plugin, so there's no worries about incorrect file ownership on shared hosting. You may have to give it FTP credentials on some hosts for it to be able to create the plugin, that's the WP_Filesystem at work, making sure the files are correctly "owned".
All this plugin really does is make it quick and easy to create a new one-off plugin and take you directly to editing it. Cowboy-coding at its finest.
Because I frequently spin off new plugins in order to paste simple code snippets into handy places. I know the code works, I've already tested it. Having to then encapsulate it into a plugin, fire up Filezilla, navigate, upload the plugin... It's a pain. This gives me an easy way to create a new blank plugin and go to the editor to paste in the known working code.
If you paste in non-working code, or decide to use the plugin editor to experiment, then you'll likely break your site. So don't do this if you don't know what you're doing. This is a power user's tool.
Then modify the plugin however you like to do whatever you want. Don't bother me with it. This plugin does what I want it to do.