At least the boy bandits have some honour since they haven't sold the girls as slaves. But they should still plan their highway robbery operations more carefully.
@Heucuva
I translated the chapter for myself in Brazilian Portuguese and the Kanji is "Sonar" in fact.
Besides, the LN Vol 4 citation says:
"That evening, I was on the late-night watch with Nana.
Since there weren’t any animals or monsters around that would harm us, I
decided to do an experiment I’d been meaning to try for a while. Just to be sure,
I asked Nana to use her Foundation Magic spell Sonar to keep an eye on our
surroundings."
@herpderp357
In the WN, Satou hunt some Spider-Bears to feed this children and clean a field crop for them.
But actually, in regards to the LN, if you keep going just after the part you quoted: "I went outside the igloo-style Shelter wall and began some prep work."
That's the reason why I was asking if it was Shelter rather than Sonar. And Sonar is a detection spell, while Shelter is a barrier spell - so when the text says "Just to be safe, I also erected a barrier using Sonar," it didn't make a lot of sense, at least to me. ?
This particular robbery attempt depends very heavily on the people you stop giving half a shit about running over thieves just because they're kids. They're lucky it was this group they stopped like this. Although, frankly, a few less mouths to feed would probably help them too so I guess they don't have much to lose.