Hehe, more Drew headcanons!!!
Drew left on his journey when he was 8. (idk how the laws work in LaRousse City but I like the idea of him leaving earlier then most trainers do. The reason I came up with (which is not canon at all lol) is that as long as you catch your own pokemon instead of being given one by a professor, you allowed to leave once you turn 8.)
While Drew always planned to be a pokemon coordinator, he had originally gone through the pokemon gyms, more so for Roselia to get stronger then to actually join the pokemon league. After he beat the first 3 gyms (I'm only giving him 3. Sometimes I have it so he can beat more, but he only as one pokemon at this point), he went on to be a pokemon watcher. (so he could get better at seeing the small things to fix for his pokemon's coordinating routines!). Then he'd go into pokemon breeding so that Roselia could look her best. Only after he was sure he could do all of those did he compete in his first contest.
Roselia has to approve of all friendships that Drew has. If she doesn't like one of Drew's friends, he'll ditch them. To Drew, Roselia and his other pokemon are more important then any human.
Drew once gave coffee to flygon back when flygon was a trapinch (he was sleep deprived and thought he was giving trapinch water). It... did not go well. Trapinch ended up digging through a wall and almost drowning in a lake. Drew made sure to keep coffee a good 10 feet away from Flygon/trapinch after that.
