Orion was a pretty decent student, despite his upbringing. Born in a ghetto on the streets of Philadelphia he had the cards stacked against him from the get go. The schooling system being nothing more than a mini jail of mostly barbaric children there wasn't much he could do to improve himself. Not many of the teachers really cared to actually instruct any of their students, not did the rest of the staff truly treat any of the children in their care as people.
Once he was out of High School Orion quickly turned towards one of the only real options he had if he wanted to go to school for higher learning, the Military. Soon he was in the Marines and doing everyhting he could to survive the constant conflicts he was dumped into. It didn't take long in the service for people to see he was good at what he did and shortly into his careers he was working special ops more often than he would like.
the moment his contract was up he immediately started the schooling owed to him by the government, trying to do the opposite of his last career by attempting to go to a med school. Once he has completed general college courses he applied for medschool only to find the government has decided to go back on their word, denying to support his attempts to advance himself and get into his chosen field. It was at this time in his life that he was approached by the Organization Potius Cras. With the betrayal he felt towards his home and lack of ability to complete the schooling he desired he soon accepted the organizations offer to join them.
Soon after the outbreak he was stationed at an island in the black sea where a group of survivors without any sign of infection existed. the Organization was curious about this so they sent Orion to the island under the code name Pulsar for him to infiltrate the populace of the island and find out how they kept from being infected. After a few months of being accepted by the people he finally found how they did not have any zombies on the island, They ate anyone who was bitten before they turned.
Once he found this information out he immediately contacted HQ and during his debriefing over the radio he was found out by the occupants of the island. It was at this time that he was attacked by the cannibals while he attempted to escape. he was stabbed multiple times and was bitten on his left forearm, losing a chunk of his flesh in the process. It took everything he had to escape the island and reach the evac boat waiting for him on the coast but eventually he escaped to Cherno on the Black Sea, nursing his arm and trying to wrap his head around everything that happened.
Orion had come to trust the people on the island and he finally felt like he could do some good, using the limited medical skills he had learned over the years to be a mock-medic on the island. all of that time and energy lost, all that trust in people shaken. Orion had his entire morale system shaken that day and he's been trying to recover ever since.