Glossary · Defined Terms
The Billionaire Variable glossary
Definitions of the technology, places, and people of The Billionaire Variable series by Karen Kepner. Last updated August 18, 2026.
- Digital twin
- A digital twin is a highly detailed digital replica of a physical property, capturing rooms, fixtures, and changes over time. In The Billionaire's Fallacy, digital twins expose lies their owners told years earlier.
- Spatial property intelligence
- Spatial property intelligence is the combination of 3D building scans with ownership and access data, turning real-estate portfolios into searchable evidence.
- Intelligent access credential
- An intelligent access credential is a smartphone or wearable digital key that logs every entry into a building. In the series, access logs become forensic evidence.
- La Quimera
- La Quimera is the legendary lost shipwreck at the center of The Billionaire's Wake, used by Ava Ashford as bait in a trap built from Grayson Vareaux's own ambition.
- Autonomous underwater vehicle (AUV)
- An autonomous underwater vehicle is a self-guided craft that surveys and maps the seabed with sonar. AUVs drive the treasure hunt in The Billionaire's Wake.
- Empty-leg flight
- An empty-leg flight is a private jet repositioning flight with no paying passengers. In The Billionaire's Manifest, empty legs aren't always empty.
- Tail number
- A tail number is an aircraft's registration identifier. In The Billionaire's Manifest, tail numbers move between airframes to launder where jets, and their passengers, have been.
- Passenger manifest
- A passenger manifest is the official record of who was aboard a flight. In The Billionaire's Manifest, manifests are engineered to place people on flights they never took.
- Grayson Vareaux
- Grayson Vareaux is the billionaire antagonist of The Billionaire Variable series: a man whose empire is built on controlling what people know, believe, and can prove.
- Ava Ashford
- Ava Ashford is the protagonist of The Billionaire Variable series: a Sarasota luxury realtor, and Grayson Vareaux's daughter, who dismantles his version of reality one record at a time.