Both are xianxia dramas in which the MLs are demon lords, and the FLs immortals who have a past life connection to the ML. Both SMLs are the FL's master who she is devoted to but has secrets of his own. Both plots have the FL thinking the ML betrayed her and later discovering the higher immortals are manipulating her, pushing her into killing the ML as she did in the past.
The Sun in the Dark feels like a low-budget remake of Love Between Fairy and Devil, but is still different in some ways and very fun to watch. In both dramas...
- The FL has an unknown identity and is underestimated in the immortal world;
- The FL hides the demon lord in the immortal world, and is later brought to the demon world;
- The ML is heartless at first, but protects the FL;
- The FL and the ML are bound by a spell/artefact;
- The 2ML is a high-ranked immortal.
- The FL has an unknown identity and is underestimated in the immortal world;
- The FL hides the demon lord in the immortal world, and is later brought to the demon world;
- The ML is heartless at first, but protects the FL;
- The FL and the ML are bound by a spell/artefact;
- The 2ML is a high-ranked immortal.



