Context: In this world, you can extract your memories and either share them with people or use them as weapons. The story takes place on an earth analog world and the time period is the 1700-1800s, but the technology is very intertwined with the magic.
Arthen has perfect, photographic memory, and i wanted to really explore what this "power" actually meant in the context of the world. Firstly, he's probably top 2, top 1 smartest in the verse. Granted, that's not saying that much, but since he remembers everything, he can manipulate people (hes met before) exceptionally well. But despite basically being a master manipulator, he's kind of forced to be a good person by his own psyche. Since he has perfect memory, he also remembers his own feelings of guilt if he does something morally wrong, and those feelings compound on themselves over years since they don't fade over time. At the same time, he can't fall in love or form genuine connections because his feelings of grief when those people die or otherwise leave ALSO compound over years. He also can't participate in magic the same way as everyone else. His memories are usually pristine (so perfect for military espionage), but he cannot view others' memories because it erodes his sense of self. Basically, he remembers the other person's memory in the same detail as if it were his own, so the line between "him" and "them" becomes blurred. Like, if he views the wrong memory, he could very well end up in love with someone he's never even seen before, or end up with someone else's insecurities/goals/ambitions/etc.