In the early volumes of Sakae Saitō's post-apocalyptic landscape bike tour, we met Youko, a young human, and her companion Airi, an artificial humanoid of some kind, who are traveling around Japan on a Yamaha XT225, known as the Yamaha Serow. This small motorcycle allows for off-road and street riding. With no people to repair infrastructure, roads, and bridges are becoming increasingly unusable, but the off-road capable Serow allows Youko and Airi the freedom to get to most places that are on the main island.

Youko and Airi survive by hunting, fishing, trapping, and scavenging buildings. With wildlife living freely in the remains of human spaces, they don't have the kind of food shortage that plagued Yuuri and Chito in Girls' Last Tour. They cheerfully visit places that would make great destinations in the present. What they don't find is other humans. Just a few robot bodies and automated systems. Remnants of human society.

Volume 4 turns a little darker, if you can imagine. Both Youko and Airi now have visions of places they are visiting, but they serve primarily to make the landscape feel even more ruined and abandoned.

Volcanic gases overwhelm Youko from a live volcano – by itself, it can't be the answer, but maybe it is part of the story as to why everything is ruined. Airi sees what she imagines to be another human.

In Volume 5, we learn that the person they met, Eight, is yet another android, specifically built to rebuild the town after a disaster. Having nothing else to do, Eight has refurbished the town's medical facilities, created a hydrothermal generator, and run a farm. Despite this, Eight has never seen a human, said hello, been thanked, or even talked with a person until Airi and Youko arrive.

Yoko's condition puts an end to my conjecture that she, too, might not be fully human, which then begs the question – how has she, alone of all humans, survived the end of the world…and why does it not cause any emotional impact, except as an observation?

Eight turns out not to have originally been designed for the preservation of human life at all. How he came to be there, and what he really should be doing, is a whole other puzzle. His own answer to his conundrum puts Youko in danger. Even after that, Youko's optimistic outlook means that she still thinks of him as a friend.

Volume 6 takes us to the days before the story began, with Youko and Airi in the shelter. Which brings up yet another question – how long were they in that shelter? When did they get there? Airi says they were always there…but what does that mean? We see their memory of the person Youko calls “onee-chan,” we see them being trained by the bots of the facility to be able to survive, and the day they were able to leave the shelter, but that doesn't tell us anything about what happened.

The two continue their travels, and by this point, I'm paying attention to the details of the destruction of humanity. Windows are blown out in buildings and vehicles, so not an EMP. Cars are parked in lots where humans left them at offices and tourist locations, so not something they could escape. Airi and Youko continue their travels, scavenging, living off the land and the remains of humans, and learning about places. Youko's visions continue, which motivate her to try things, like resurrecting defunct fireworks to see one, trying alcohol, or even hunting for a cryptid.

I have to give a lot of credit to Saito's art. Every scene is filled with detail. A ruined marine center has tools that can be used, wildlife living there, clothing, and snacks in the shops. But everything is damaged. Rust holes pockmark the metal, grasses and trees grow up through the walls and floors. It is an extremely careful, fully-imagined landscape, and one has to admire the eye of an artist who can see a beautiful landscape or tourist locale…and imagine it almost wholly destroyed.

Youko gets a “stamp” at every location, which is actually something that one does as one tours around Japan. There's usually somewhere at every sightseeing place where you can get a big ink stamp for your book or, more commonly, a QR code to get a digital stamp. Every chapter in this series comes with a QR code for that location, customized by Saito with Youko and Airi. When you click the link, you get a stamp for the town, with the logo of the series social network for motorcycle touring “Touringram” and Airi and Youko, who say “Stamp Get!”. It's weirdly satisfying as the series continues, making you feel as if you are part of this trip.

On the positive side, Youko and Airi wandering around Japan on a motorcycle does make me want to visit more random touristy places – I actually love doing things you're “supposed” to do and going to places you're supposed to see, but mostly, I love cheesy gift shops. On the negative side, I can't stop thinking that any questions or answers about the end of everything will completely ruin the vibe, but how do you not ask the questions or want some answers? “People of the past” carries a lot of water here. Youko “sees” these places at their heyday, but doesn't feel any loss, likely because she's only ever had Airi as a companion.

As we head into the last two volumes, the questions are piling up, a new sign of “life” has appeared, and I'm relaxing into the idea that this series may end, and we will never know what happened.