It was Jaden from Yu-Gi-Oh!...the strangest part is, I've never even watched that show. I was very young and found to him to be absolutely attractive. (Saw him on a friend's YouTube account).
Sometimes it's hard to remember exactly my first 日本动漫 crush if I recall correctly this time was Masaki Anzu from Yu-Gi-Oh! (think her name was 茶 或者 something like that in the english dub..)