Touma and Yui meet, and after circumstances force them apart, they seem to carry on a quiet romance through love letters, each longing for the other across the distance. What begins as a simple romantic story takes an unexpected turn near the end. Every line of dialogue turns out to come from letters the public sent to Morinaga after the company announced in March 2022 that it would stop selling Lipton Milk Tea. The short ONA is a commercial directed by Toshitaka Shinoda to celebrate the drink's return in carton form, and its title refers to the 667 letters fans mailed in between April and September 2022.