One user with several profiles (pages) What modules are available (profile2 would come in handy i guess) to create something like pages on facebook.
Like on facebook each containing description, galleries and some other content i make available.
All handled by user who created pages.

I have idea in theory how would each user create pages, but i have no idea how would he for example when uploading gallery tell Drupal that the gallery he just uploaded belongs to page 3, while this user has 10 pages.
The 'edit own' permission should be all you need. Allow the user to create content of a specific node type. Put a gallery, description and any other fields on it.

A little more detail:


Create a content type 'Pages'.
Make sure users can create new pages and edit own pages.
The user makes as much 'Pages' as he wishes.
Put a gallery and any other fields on the content type.


If you want to use other content types instead of fields, use entity reference.