Before Larry, the Negative Spirit was just a jumble of energy, one part of a larger, sentient nebula made out of that same energy called the Negative Nebula. On the day of Larry’s test flight for the X-15, it separated from the nebula and bumped into Larry’s plane in the Earth’s upper stratosphere. This collision caused Larry and the Negative Spirit to merge and caused the plane to fall, sending them hurtling to Earth. This accident left Larry severely burn-scarred.

Larry was so close to being accepted on the Mercury Mission when during one of his flights he had an encounter with the Negative Spirit. In this incident, the Negative Spirit merged with him and caused the ship to crash. Larry was left with burn scars covering his entire body. In addition to this, Larry was possessed by the Negative Spirit. Larry also permanently gives off radiation that kills anyone any of his bare skin is exposed to. Over the next several years, Larry and the Negative Spirit were tortured and experimented on by the Bureau of Normalcy. 

After a while, they end up with a man named Niles Caulder, who is the one who gave Larry the radiation-proof bandages that allow him to have somewhat distanced contact with people. He lived in Niles' estate, called Doom Manor, with a group of metahumans helped by Niles Caulder, although it turns out Niles was also the one responsible for most of their "accidents" as well, but they don't find that out until much later. 

This group of misfits are far from a team of superheroes. They all have varying types of trauma that makes it difficult for any of them to get anything done. Most of the time when they save people, it is from a disaster they caused in the first place. Despite this, as more superhuman and/or nonhuman things happen around them, they are forced to attempt to put their "super" skills to use and work as a team to save themselves and the people around them, and most of the time they stumble through it rather successfully. 

Relationship: Larry Trainor (host)

Idiots with really bad communication skills despite being bonded to each other for 60 years. Codependent but also not super thrilled about it. Neither of them signed up for this but they need each other to survive. Larry’s got so many issues and he’s an “I want to mind my own business please leave me alone” wallow-in-self-pity kind of guy. The Spirit is quite a bit more heroic than Larry is, and while it looks after its own interests (and Larry’s, since they need each other), it will also definitely help those in need even when Larry doesn’t want to. They usually communicate by Larry talking out loud and the Spirit writing a note, but the notes only ever contain one or two words at most. It cannot talk out loud, and most of the time Larry would not be able to know if it did or not, since for most of his relationship with the Spirit, he immediately falls unconscious when it flies out of his chest, and both are in danger of dying if it does not return in a short period of time. It has a mind of its own and decides to do this whenever it wants, often at inconvenient times for Larry. It can communicate with him telepathically, but not through words, by projecting and manipulating memories or fantasies, which leaves Larry to figure out what it’s trying to communicate by these dreams. Sometimes it is connecting Larry’s mind to someone else’s in this dream-state (usually someone important in his life, like his former lover John or his son Gary). Their relationship improves as Larry works through his trauma and depression and works on accepting himself, and with time and practice they are able to separate for longer periods of time without Larry falling unconscious. I think the comedic and dramatic elements of Larry losing consciousness when the Spirit leaves his body could be fun to work with, although Larry is a lot less functional at this point in his timeline.