Teacher x Student Romcom “Tsuruko returns the favor” vol 3 by Yokoyama Hidari
A strict high-school teacher visits a fairytale themed cafe to hear about his dead sister who seemed to work there in secret.
Hesistant at first, he gets along well with an insecure young girl working there who soon after turns out to be one of his new students!
(Tsuruko no Ongaeshi)