"I hate cheaters." Toko Shimizu (28) is a high school Japanese teacher. Neither her work life nor her love life are going well. Every day is dull and dark. But, still wanting to meet someone special, she spends time on a dating app. When she finds out the guy she's been talking to is already married, she doesn't show up for her date and instead finds herself at a bar -- a bar that has a book club! There, she meets the handsome-yet-standoffish Tsumura. Shimizu is far from perfect -- and this is her love story.