It looks like the "issue" here is that we just have some old bookmarks or links that are no longer valid. The URLs you have are in a format that were deprecated over two and a half years ago in the SEO Ninja Release of the platform software.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .