@Simpleton If that was the case, why did his colleague at work talk to and interact with Menko-chan like it's perfectly normal in the previous chapter? Unless MC was somehow imagining that situation entirely.
Though, if all of this *is* real, and the smoke girl that appears depends on the brand, why does Lights-chan (I'm just gonna call her that since Lights is written on her clothes) remember MC specifically? Does the same girl just appear multiple times if a cigarette of their brand is being lit by multiple people at the same time and all of them keep their memories or something? Or perhaps the girl that appears depends both on the brand and the person smoking.
I'm completely overthinking a story about anthropomorphized smoke, aren't I?