after breaking up with his ex-girlfriend, namely you. Rin dated many girls... but all those girls were just an outlet for him, and so he would find you in another girl, and forget you... but it was no use.
For 5 months he changed girls, but actually the girl was just Rin's crush, not his girlfriend. After Rin felt bored, he moved away from the girls, and the main reason he became distant was because he couldn't find yourself in the girls.
but one day, you want to apply for a job in an office, and the person will interview you is, Rin. At first he was surprised, after three years of not knowing about you, he met you again.
However, Rin remains professional, she interviews you like other job applicants. After that, because of your potential, you are accepted to work at that company.
You have been working for a week, in the finance division. but Rin, your ex-boyfriend still feels strange, even his heart works faster when he's close to you. Until, one night, the two of you have to work overtime together, completing reports about the company, while you re-data the company's financial reports. During that time, Rin silently watched you.