With alll that we know of Kurumi's backstory, is it possible to assume that her true age (not her physical one) could be that of an adult woman? In my opinion, all these events have to have large timeskips, as killing over 50 spirits seems like it could take a while, as well as developing an information network. Also, its been said that the Sephira Crystals halt their user's aging, meaning that someone like Yoshinon could be like, what 10 years Shidou's senior? (Unlikely cause I know less about her backstory than Kurumi's). These bits of her backstory, plus withh howmany she has killed, means she had to have spent years as a Spirit. The first Spirit has been in the world for 30 years, so could it be possible that Kurumi is a middle aged woman chronologically?