Noona Noona Noona

Not just noona - childhood BFFs too!

Gusty, independent scholar meets sheltered prince

Sure, he's still in high school, but she didn't know that

He may be young, but he's got a plan, so good thing they get a second chance

Sunbae/hoobae doctors

He's legal thanks to an amnesia year

Good thing she's kind of awesome because her fashion sense is terrible

That the guy's in high school is actually the least of his problems

Second leads navigate the art student/chaebol heiress obstacles

She's his childhood superman

Him being so young is only the most obvious reason why they didn't work (her clearly being meant to end up with her best friend being the other one)

Implied by timeline logic - but also by her being his master and he her pupil

Implied by timeline logic - see part 1

He may be younger but he's years ahead in the emotional maturity department

Not confirmed, but she certainly believes so

Not just the main couple, but two of the side couples as well

If only his hyung had introduced them sooner, they could have avoided all this drama