Well since my concept is a hunter I though tinkering traps make the most sense, I guess that if we both take it that would be a good reason on how the two girls got to know each other/work together although if it is preferred not to have the same I think I should change since Ampere said she was interested in magic first. I think I could go for Demon summoning claiming that it has something to do with her hunting abilities beyond just summoning a helper, maybe something like summoning the inner demons of those she has captured? :P  Or what is shamanism all about? I also thought there would be more magic options since you mentioned why not taking it, or is that there are several choices within each of these 3 disciplines?