A co-worker was wearing this t-shirt so I asked her what the writing was. She didn’t know what it says but I got the idea from the graphic that it was something about Chikan.
In case you’re not familiar with the word “chikan,” it’s a Japanese version of “frotteurism,” which is the act of groping, or rubbing of a non-consenting person for sexual gratification. More specifically, “chikan” usually refers to this act in public, like on crowded trains, buses and elevators.
If you look at a close-up of the graphic on this t-shirt, you can see that the male on the right is groping the female on the left. They are riding a train because they are both using the type of hand-straps that are available on Japanese trains.