Honestly i dont really know. I never really watched anything from the occasional dragonball episode or pokemon growing up. I liked japanese games and hated spanish class when i was in highschool so i said fuck it and took japanese instead. I tried getting into anime, watched trigun and loved it but that was about it. In my last year of highschool i actually got to go to japan to tour with a local symphony orchestra i was playing with at the time and the girl i spent most of my time with in my host family was a complete fujoshi, but was awesome. she took me to akihabara, i went on a date with her friend, showed me around and introduced me to otaku culture. I started getting interested in it then. In the next couple years i watched a couple of the classics, azumanga, read all of FMA that was out at the time (still need to read the last few volumes), and it kinda simmered. Then i found the world of buying manga from my used book store. It all went down hill from there, well that and watching panty and stocking. Now i have easily 500+ volumes of manga, 60+ figures, japanese books games, 2 dakimakuras, ect. and i dont regret it one bit.
tl;dr - a fujoshi in japan got me into anime.