Story
Ryuumaru, a high school boy, likes to go to Senda Shokudo with his friends, because the kind-hearted restaurant owner lets them keep a tab. They feel free to fill their stomachs, and they go there so often that it almost feels like a "hangout where you can eat for free.'' One day, after some time has passed, Ryomaru comes into a sum of money, and he goes to Senda Shokudo by himself to pay their bills. But for some reason the door is closed, and the restaurant remains silent without a sound.
Synopsis via AniList (English).