Adrian comes from another Earth dimension, just like Usagi and the TMNT. For most of his childhood, he lived in peace with his family and friends, but in the year he became 12 years old, a civil war started. Since then, Adrian and his family had to heal many civilians from the fights.
The thing is, when they'd heal someone, part of their lifespan and energy would be gone. The bigger the injury, the more energy they'd have to use. And since Adrian was the youngest, they'd make him heal most people because he had the more energy to spare and they were old. So he spent about 5 years doing the most healing, while his family rested.
He'd trust his family less and less because he was so, so tired. But they didn't want him to stop, and if he did, most people would perish.
One night, he'd overhear his parents speaking on the matter; they'd say it was better for Adrian to do all the healing because they were much older than he was, therefore they wouldn't die so soon. This made Adrian extremely upset and hurt, so he took his late grandma's pendant, stole one of their neighbor's ship, and flew away.
So now, Adrian is a traveler between worlds. He mostly does this, not only because he wants to know about the universe around him, but because he never felt quite at home and didn't have enough freedom to do much. During this time, he learned that most aliens had names instead of code numbers, so he changed his name from Number 914812 to Adrian.
In a bid for freedom, he also managed to get himself causing a lot of trouble, only because he was forced to help others against his own will. He also sleeps. A lot.
He went to watch the Battle Nexus, where he met Donatello and Usagi right after they saved the Damiyo’s life – Adrian had been exploring because he got bored. Right away, he’d recognize Donnie because he was one of the first contestants to lose and immediately mocked him in his mind. However, he felt like it would be a good courtesy to say hello to both Usagi and Donnie.
What Adrian didn’t expect was for Donnie, who he thought he was a complete loser, to be so soft-spoken and polite – in fact, his voice immediately caught him off guard. He’d keep talking to both of them while Splinter wasn’t free from the dungeon. Usagi was interesting, but in the end, it ended up being just Adrian and Donnie speaking.
Donnie’s charisma had absolutely made him struct by him. Donatello talked about what he does (his inventions) and Adrian talked about the exploration he did across the universe – which left Donnie pretty much interested. It ended up being a quick friendship, with Donnie inviting him to Earth so Adrian could show him the different worlds and they could explore together.
A week later, Adrian showed up, they planned cool planets to visit (that Adrian knew were safe). When out of missions, Donnie would manage to contact Adrian and would spend more free time with him than his family (much to everyone’s annoyance). One of the planets they visited was populated by tiny, cute, fuzzy people. However, in the middle of their trip, they were struck by a hurricane, leaving the tiny aliens' houses mostly destroyed.
Donnie immediately offered himself to help, while Adrian kept his distance, questioning why would Donatello help so many people that he didn't know. This ended up with Don explaining to him that it is good to help people in need. It makes them happy and rely on you, and you feel great about your doings, but that if Adrian didn't want then he shouldn't be forced to do it.
Seeing all the little aliens happily bouncing around his friend, Adrian, reluctantly decided to help fix a table - which he did an okay job with. Seeing everyone happily thanking him made him realize that maybe... helping others wasn't THAT bad when your health wasn't on the line for your selfish parents. He looked fondly at Donnie - he was so happily helping others that Adrian went from having a crush to completely fall in love with the guy.
As an adult, Adrian travels around the dimensions searching for rare artifacts, while being a doctor in his spare time, for he practices herbal medicine.
He lives with Donatello and they both adopted a daughter, a mutant chameleon named Roxy.
- Adrian is from an alternative dimension called Earth 4.
- He was so mistreated/neglected by his own parents, that he ran away from home using his grandmother's pendant.
- Started travelling around dimensions, causing trouble so he could survive.
- Met the turtles in the Battle Nexus Tournament. Met Donatello there, quickly became friends and he fell head over heels for him.
- Eventually, they started dating!
