I'll openly admit I crush on boyish girls/nb femme people. Plus, I dig the sorta creeper vibe I get from her. I don't totally understand why, but I just do.
That said, I know plenty of girls who were not the "hottest" girls in their freshman year, but really hit their peak later in high school and in their 20s. Janna strikes me as the type of girl to have a similar sort of "glow up" in her late teens. It's common for a lot of people, I'm sure a lot of anons, male and female, here had a similar experience.