Jenny Hargreaves was a senior technician with the Explorer Federation at Jupiter Orbit Dock during the construction of the Celestial Fleet, the first extrasolar colony ships. Due to a still undiagnosed psychological condition or Angel malfunction prior to the launch, she was deemed too great a liability and was removed from her post. When she returned to work, the Explorer Federation assigned her a menial job in a Free City cafeteria, since when all her requests to return to skilled work have been denied. Since the event, she has despised her Angel and rarely uses it.

Lance Petersen was Jenny's superior on the Celestial Fleet project. The two had a romantic relationship up until her dismissal, but while Jenny was in hospital, he chose to leave the solar system on board the EFS Moon Seraph. Though she has still not quite forgiven him for the circumstances leading up to her dismissal, she still believes that Lance had her best interests at heart. What is still not clear is what connection Lance had to “Bug #23691”, and what that in turn had to do with the voices in Jenny's head.

José Emmanuel and Junko Iwatari are the kind of couriers that don't ask questions (although they often do a bit of research of their own). José is the face of the operation – a reckless ex-Special Forces pilot with a good reputation amongst corporations and criminals alike. If you want something moved from A to B without anyone noticing, he's the guy you want. If José is the face, Junko is the brains behind it. A former network security operative, she knows the ins and outs of corporate systems across the solar system. Often their cargo is data, and to get it to B, it sometimes has to be… forcibly removed from A.

Shinsei Hikarigawa is a young man just beginning his career as a neuroscientist with the Illuminated Research Corporation on board the EFS Star Child. Born five years after the Celestial Fleet left dock, he has never seen the solar system or set foot on a planet. Unlike most of his peers he likes to talk out loud to his Angel, and thus became unexpectedly trendy when that was briefly in fashion. He is polite and quiet but enthusiastic about subjects he enjoys; the quintessential geek.

Johann van der Kierchoff is a friend of Shinsei, and son of Captain van der Kierchoff of the Star Child. Leaving school at the same time as Shinsei, he joined the Explorer Federation in the hopes of following in his father's footsteps.

Tom Fairchild is Shinsei's mentor at Illuminated. A short, stout man with an incredible and often-used grin, Tom is the definition of 'casual'. From his clothes (perpetually untucked and unironed) and his hair (long and greasy) to his mannerisms and informal speech, nothing about him would impress a manager. However, he's well-liked by his fellow scientists, and his knowledge and enthusiasm for the field of neuroscience and for the Angel systems is unmatched.

Xiao Wing and Alexandra Harrisson are Shinsei's neighbours.