The fastest way to level up in BDO changes between quests and mobs, depending on level. Purple colored mobs give the worst XP because there is a difficulty penalty in place.
It isn't a child though. The game has tons of Shai NPCs that are also not children and have been handling that years before your rather late "first look" Don't claim to care about lore when you clearly dont.
I'm sorry you feel that way. I am looking at this from a gamedesigners standpoint as the model they created is based on a childs anatomy, I've never claimed to care about lore because I care more about the design aspect of games and the thought process behind them. This was a personal first look for me as I stated in the video, the class came out a while ago. I don't claim to know everything about the game, as I don't, at all. This was just an opinion on everything that I saw for the first time.