Adachi and Shimamura happened to meet each other on the second floor of the gymnasium as they were skipping class. Eventually, they started seeing each other more and started playing ping-pong together.
"We shouldn't be doing this!"
hätte die eine die andere gestoppt
“¡No deberíamos hacer esto!”.
"No deberíamos hacerlo" o algo así.
elle aurait stoppé l’autre
avrebbe detto "Non dovremmo farlo!"
"não deveríamos estar fazendo isso!"
сказала бы, что так нельзя.