"That person only comes on the second and fourth Tuesdays." Ritsu, who works at a coffee shop, is in love with a customer. A strong appearance that does not match his personality. Their age and occupation are unknown, but still a person she's interested in. "I want to know more about that person." A love story that begins with "I don't know anything" that you cannot find with a dating app. A beautiful waitress and a mysterious man. A pure love story between adults begins. 「あの人は第二第四火曜日にだけやってくる――」。喫茶店で働く律は、ある男性客に恋をしている。カタギに見えない、強面な外見。年齢・職業不詳。だけど気になるあの人のこと。あの人のことをもっと知りたい――。 マッチングアプリでは探せない、「何も知らない」から始まる恋。美人ウエイトレスと謎の男。大人同士のピュアなラブストーリーが始まる。