First of all, it can be used as a metaphor to describe beautiful and ugly things, such as love, which makes people feel beautiful, but also makes people feel painful and betrayed. This double-sided feeling can be called "the devil from heaven".
Secondly, it can also be used as lyrics to express the pain, uniqueness, dedication and sacrifice in love, as well as those stupid things done for love. Now it has become a secret in my heart, which makes people feel helpless and bitter.
Generally speaking, The Devil from Heaven expresses a feeling that beauty and ugliness coexist, full of pain, betrayal, uniqueness, dedication and sacrifice. This feeling can be caused by many things, and the specific meaning may vary according to the context.