What is the moment that makes you feel warm in a strange city?

I remember it was a few years ago, when I just left school, and I chose a city far from home. It was one morning and I was on my way to catch the subway. Now I forget why. Anyway, I remember being in a particularly bad mood that morning. And just when I was particularly distressed, I saw a scene that I was particularly unforgettable.

Those are two old men with white hair. They look about 80 years old. They bent over and seemed to have walked for a long time. The old lady seems a little tired. At first, she walked faster. Maybe the old lady said something, so grandpa's steps gradually slowed down. I didn't feel anything at first, but suddenly I saw two old people holding hands, and then I saw their eyes looking at each other and talking to them. And that's because the acceleration of catching the subway has slowed down slowly, so I silently walked behind the two old people and felt the warmth they brought me at this time. And that originally agitated mood, also got some relief in an instant. At that time, I was thinking that I could work hard with the people I want to love and live an extraordinary life for the sake of daily necessities and vinegar tea in my life. When I am old, both of us can't walk, so we can help each other to walk slowly.