Not an anime but a manga! I remember that I had the biggest crush on Shinya from Watashi no Messiah-sama (old I know xD). But idek. Edit: Ah, actually I may or may not have a crush on Ikuto first from Shugo Chara
From manga, actually, Kaname Kuran... ^^ cause I didn't watch the anime first~ but Takumi Usui (from both manga and anime) as well haha~
Seiya Kou from Sailor Moon. I was and still am in denial about his sex (Seiya's female in the manga as far as I know, while in the anime he turns female as a Sailor? I was too confused to care and was quick to accept any kind of Ranma logic in anime). Anyway, I was tired of Mamoru never being around and always in need of saving, so I was really into Seiya who was around to tease/romance Usagi, and I was a teen who fed on romance. And he made a much more interesting character than Mamoru, sigh. And my next crush was Zelgadis from Slayers. And then Heero from Gundam Wing. Kaworu from NGE. Later, I was too busy BL shipping the male characters to crush on them.
Kakashi-Sensei and Levi Fucking Ackerman As for the girls, it would be Mikasa Ackerman, Saber, and Sailor Mars Honestly, don't know which was my first. Probably Kakashi.
I was like a few of you, it was Tuxedo Mask/Mamoru. Though back then, he was Darren because of the English sub.