The young prince Pietro of PopoloCrois and his forest witch friend Narcia are playing one day when GamiGami Maou – the self-proclaimed arch nemesis of Pietro – initiates a scheme to take over the kingdom. When his plan to switch his castle with that of PopoloCrois backfires, it creates an explosion in the middle of the forest. Amongst the debris, Pietro and Narcia stumble across a young girl, though before they can find out who she is, GamiGami Maou attacks them! Luckily, the power of the dragon blood within Pietro saves them and they are able to restore the forest to its original state before returning home. They later find out that the mysterious girl is named Hyuu and she is one of the wind-kind, a race that died out many years ago. With very few memories of her previous life remaining, Hyuu and Pietro are determined to discover the truth behind the fate of Hyuu’s people, and find a way for her to return to her own time.
In a massive online world, people act only as well as their conscience demands. When one player's punishment is to be trapped in this world, a disparate group of people seek the answers why. Their motives are varied; their methods even more so. What stands between when we tear down the walls of reality? Where does our soul end and we begin?
Both .hack//SIGN and PoPoLoCrois Monogatari place heavy emphasis on their characters' developments, greatly slowing down the story in many instances to focus on them. Some more trivial similarities include their fantastical settings (With SIGN incorporating heavy sci-fi elements as well) and the fact that they both tie in with related video games. SIGN is a much more 'grown-up' series than PoPoLo, but don't let that put you off either series!
Kosuke and Rikimaru are the two young guardians of Konpei Island, home to the last surviving dragon on Earth. It is their job to look after the dragon, which they named Pochi, on a day-to-day basis, from ensuring its safety to taking it a basket of oranges to eat. One day, when Sakurako, a professor from Tokyo, comes to the island to research the dragon, the two boys act as her host and guide. However the situation takes a turn for the worse when a collector named Yamada arrives on the island to kill Pochi and take the stone on its forehead. Now it's time for Kosuke and Rikimaru to show what they are made of and fight off the intruders, including Yamada’s hired goon, Michael Commando, and save the life of not just Pochi, but of all the residents on Konpei Island!
While both of these series have rather different plotlines, they both give off a similar sort of vibe. They are both fairly family-friendly adventure series, and though Popolocrois is more of a fantasy, Kosuke and Rikimaru also has elements of the fantastic about it. If you enjoyed one of these series, it may be worth trying the other.