Yes, I recommend Primeval Chaotic Heavenly Lord and Eternal Emperor of God, these two fantasy novels. The main character of "Primeval Chaos Heavenly Lord" refused to accept the restraints of the Great Dao and transcended the Great Dao to establish his own world, while the main character of "Myriad Ancient God Emperor" also transcended the Great Dao through divine power cultivation and achieved supreme divine power. I hope you like my recommendation. Muah ~
The main theme could be about the exploration of the supernatural or the afterlife, as 'beyond' often implies something that goes past the normal, physical world. And 'black' might symbolize mystery or the unknown in the context of the novel.
I'm not sure specifically as I haven't read it. But it could be about self - discovery, relationships, or perhaps a journey through different times and places based on the title.
Another possible theme is redemption. The 'darkness' could represent past mistakes or sins, and the story could be about the characters' journey to move beyond that, to find forgiveness and a new start in life. They have to face their inner demons and then strive to be better, to go beyond the state of being in the 'darkness' of their past actions.
The Infinite Stratos manga doesn't always go past the anime. It could be on par or have a different focus. Usually, it's up to how the story is envisioned for each medium.