Actually, Rena wasn't the youngest to first clear Stage 1. Saki Suzuki was slightly older. You know, the little short-haired girl in a softball? uniform that failed the spinning log hard.
I was aware of that, however, i didn't have a enough room to say that, and besides whats the difference in a few months. Yes I agree Saki Sasuki did look like a boy. Thanks to obakemono for locking the other thread.