Itsunori fell madly in love with Karin Kitaoka, a company colleague he met at the acceptance ceremony, and approached her intensely. Soon after, the two started dating. After joining the company, the two end up working in different departments. Karin, who works in the sales department, has many drinking parties and social gatherings, and because of that, Itsunori's worries increase, such as "Is she cheating on me? Is she being sexually harassed while drunk?". As a result, Itsunori awakens his NTR attribute. I want to have my beloved and important girlfriend taken by another man! Itsunori, who cannot suppress that distorted love, decides to have her taken by a junior at university...
