Are you sure you want to use this module?

This module has the potential to seriously destroy your Drupal content. Please be aware of the following caveats before installing:

Not compatible with revisions. Creating node / entity revisions with varying paragraph relations will have adverse consequences.
Drag-and-drop between parents is not supported. e.g. moving a paragraph from a node field to a sub-paragraph field will not behave the way you want it to.
Not compatible with translations. Expect weirdness if you're using this module in a multi-lingual site.
No test coverage

Are you OK with all those issues? Tired of your database filling up with orphaned Paragraph entities? This module may be for you.

A single module file with 3 hook implementations, this module implements a naive, rudimentary approach to cleaning up paragraphs.

If you save a node (or any other entity) on which you've removed a reference to a paragraph entity, the paragraph entity will be deleted.

If you don't want to delete orphaned paragraphs, or if you're re-using paragraphs among different entities, then don't install this module.

If any of the caveats above describes your use case, then I'm afraid you'll have to wait for a full-featured resolution to be rolled into Paragraphs and Entity Reference Revision modules:
#2741937: Removed paragraph entities are not deleted from database
#2771531: [META] Remove obsolete composite entities from existing storage (garbage collection)

If you run into any other odd behavior, please report it in the issue queue and I'll add it to the project page here.

RTBC issues for Paragraphs Clean