Aijin Shikkaku: Uso wo Mou Hitotsu Dake

Wakana is a modest office lady working at a bridal company. She lacks confidence and is shy, but one day she meets a man named Akiyama by chance, and he guides her through life, gradually changing her. She thought she would never see him again, but when Akiyama comes to her company as her boss, she meets him again, and Wakana's heart is drawn to him more and more. But Akiyama is married!? An unforgivable erotic story unfolds in the office.

(Source: Akita Shoten, translated)