Beyond the veil (en Inglés) - Michael Knight

Death was only the beginning of Macy Vance-Lowry's problems.

When a freak library accident ends her life, meticulous librarian Macy awakens to a world of Ecto-Static energy and strict spectral rules. Navigating the 'Density Rule' and 'Static-Lag' is hard enough, but finding herself anchored to the very building that killed her is even worse. That is, until she meets Julian Vane-Sterling.

A charismatic ghost from the Roaring Twenties, Julian teaches Macy the art of the 'Ghost Hack'-from haunting autocorrect to the intimate warmth of Aura-Merging. But their peaceful afterlife is under siege. Dr. Aris Halloway, a ruthless scientist, has developed technology to harvest ghosts as batteries, and he has his sights set on the Grandview Public Library.

If the library falls, Macy dissipates into nothingness. Alongside a living delivery driver who can see the unseen and her grieving best friend, Macy and Julian must master their ghostly physics to thwart Halloway's machines. In a race against demolition and containment, Macy will discover that some connections are powerful enough to transcend the veil between life and death.