Saki Komatsu, a college student who works at a bar, is in love with a regular customer, Yamato Shiraishi. Despite the slight age difference between them, Saki is head over heels for this office worker. For many months, she has wished to convey her feelings to him, but her lack of courage has left her love letter undelivered for six months.

However, thanks to a small mishap, Saki finally finds the opportunity to give him her letter. The two have no prior experience with romantic relationships, leaving them unsure of how to deal with the butterflies of being in love. The simple act of making eye contact with each other is enough to make them blush. Nonetheless, day by day, the pair slowly grows ever closer in this heartwarming love story between a waitress and her customer.