The yellow Sobu Line train that passed over the overpass in the background clearly is from the 2020s because it was mostly metallic silver with a single yellow stripe. In the late 1990s in which this story is set, Sobu Line trains were solid yellow with thickly matted paint from having been painted over and over again in multiple layers for decades.
Blue flame butane lighters did not exist in the 1990s. Japanese were, however, preoccupied with Zippo lighters, which they thought were cool. This was not one of them.