Anko thought for years that Orochimaru was her angel. Sent from heaven to rescue her from her hard abusive life.
When Anko was "Abandoned" she thought that there was no heaven or angels.
When Anko grew up she began to believe in the devil and things that were evil like Orochimaru.
What Anko didn't know was that Orochimaru mused that if there was one person who could bring him back from the piths of hell it was her Mitarashi Anko.
Orochimaru was never her angel.
She was his.