Tanshin Furin -Netoraretara Netorikaesu Baigaeshi | 単身不倫 -寝取られたら寝取り返すバイ返し‐

An engineer 'Manzono Seiji' who works for an IT company goes to work alone to set up the infrastructure of the company in Serpentine City.

At the company to which he is assigned, he meets "Amagasaki Ayaka" who belongs to the support section and together they perform infrastructure work and miscellaneous tasks.

Then one day, Seiji receives a consultation from Ayaka.

It was something like, "My husband who is working alone might be having an affair. When I looked at her husband Kyosuke's social networking site, I saw that some of the photos posted on the site resembled the belongings of Seiji's wife, Yui.

When Seiji got back to his room, he was able to remotely view the security cameras in his house. That's where you'll find Yui and Kyosuke...

Seiji finds conclusive evidence that she is having an affair and decides to take revenge by cuckolding Ayaka Amagasaki.