Birdo. But that was with Wario's Woods (which called her Catherine even in America), where she appeared to be a good character. All she did was point to the time bar with a half-dazed look on her face, then when Wario was about to come, she'd flinch in surprise and disappear. Oh yeah, and if you finish a stage while Catherine's up there, she waves and winks at you as she leaves. It wasn't much, but I took what I could get.
I also had a crush on any pink Yoshi that would appear in a game (I was a Yoshi nut back then), even though all Yoshis are portrayed as male (except in the comics). I'd also come up with any excuse for thinking a pink Yoshi was female: that "Tropical Island" in Mario Party 1 had a Blue Yoshi and Pink Yoshi trying to reunite, and that the Pink Yoshi and White Yoshi in "Yoshi's Story" have the highest voices as I expected.
For male characters I thought were cute, there's Yoshi, Lemmy Koopa, and (only in later years) Bowser.
