It was the second day of Kiyono Lin's menstrual cycle—Dubian Che thought to himself—as a letter appeared on the old elm desk in the Human Observation Department's activity classroom.
The situation was highly suspicious.
Of course, it wasn't the act of writing a letter itself that was suspicious in an era where everyone had a cellphone in hand.
Maybe for many modern people, they'll never see a letter in their lifetime, but regardless of how modest Kiyono Lin and Dubian Che were, they received at least one letter on average every day.
The truly suspicious thing was that the only people who had keys to the activity classroom were Xiaoquan Aonai and Kiyono Lin.
And there was no reason for either of them to write a letter.
"Someone climbed in through the window?"
Kiyono Lin looked at Dubian Che with an expression reserved for idiots: "This is the fifth floor."
"True," Dubian Che nodded, neither agreeing nor disagreeing.
He could, in fact, do it.
