Nagi Yoroizuka, a 27-year-old system engineer at a software development company, is facing down her thirties with no sign of romance. She works hard at her job, but things never seem to go her way. Then, just when a series of mishaps leaves her at her lowest point yet, a childhood friend reappears to offer her a hand. Not only is this genius engineer warmhearted and good looking, he gets along great with her! The problem: she's only ever seen him as a friend, while he's been hiding his feelings for her their whole lives. But even if she's willing to give him a chance, will trauma from her past prove too much to overcome?