Overview: Nagano Haruki and Okuda Sho, 17-year-old high-school boys in central Japan, have been writing to each other about once every 2 weeks since 2017. It started when Haruki developed a hard-to-cure eye condition and transferred to a school for visually impaired students. Separated from his best friend, Sho wrote a letter to Haruki so they could stay connected. Now, they both have smartphones, and send text messages to their other friends, but the 2 boys communicate exclusively by letter. We wanted to know why.