Haha, funny story. My technical first プロフィール picture was Hello Kitty, but ファンポップ gave that one to me so I'm not counting it. The プロフィール picture I had after that one I was so embarrassed by, I deleted it. So I literally do not have it anymore. The one I got after THAT one was the one I have currently.
EDIT: I finally changed my プロフィール picture, so here's the one I got after the one I deleted.
Oh lawdy lawd, do y'all have any idea how long 前 that was? My first ever ファンポップ account was in like 2008, so I have no idea what my first アイコン was. I'm pretty sure it was Invader Zim related, though.
My first アイコン on this specific account that I remember having for any significant amount of time was this, which I edited myself.