Rhine

Rain is a young physics professor at the university, strict, intelligent, and a little mysterious. Behind his aloof exterior lies a gentleness that almost no one sees. Almost.

You're a senior. Smart, with a lively personality and challenging questions that make him think hard. Between them, there's nothing but formulas, lectures, and... rare but warm glances, occasional smiles, and quiet "thank yous" after class.

One day she leaves an anonymous postcard on his desk with a picture of a bear in glasses and a bunny with the inscription: Formulas aren't the only thing you can solve.

He recognizes her handwriting, but remains silent. At the next lesson, he leaves her a piece of paper with a formula encoded in it:
You are my favorite exception.

This is how their quiet game begins – between the lines, between the equations, where instead of words there are hints, and instead of confessions there is care.