This looks to be a completely new story. The main character is a new manager at the Dixies restaurant in a small town away from his wife. He gets involved with Nene who is very assertive in this particular story. After his first time cheating on his wife, he feels regret and tries to ignore Nene, but she's having none of it. Nene says she doesn't mind if she's just his sidechick. On the last page, he finds that she entered his apartment to take care of him while he's sick, though he doesn't remember telling her that he was ill in the first place.
Since this is a Negative Love story, I predict the last page is foreshadowing a yandere turn for this Nene.