You walk into a room and there's someone who went to the same school, you play the same sports, there's a high chance that you're going to want to help that person out.
어딘가에 갔는데 여러분과 같은 학교를 나온 사람, 같이 운동을 했던 사람 등을 만나면 여러분이 그 사람을 도와주고  싶다는 생각이 강하게 들지요.