Maybe you had previously deleted apps that hadn't used enough data to appear in the statistics, and so didn't see this (this would also apply if you only used them with WiFi, since that is counted separately from mobile data).
Anyway what I'm saying is based on more than a decade of using Android. This is how the usage stats display data used by apps that have since been removed, and it is by definition only historical usage because an app that has been removed cannot use more data. Wait a couple of weeks and it will disappear from your statistics unless you remove more apps that also used mobile data in the meanwhile (in which case any data used by those apps will appear as a new "removed apps" entry).
What do you actually think this is? That's what I don't understand.
The icon for the app you have ringed is the default icon for apps which don't have an icon, which are usually background system apps but not always. Different manufactures add different things in different models, so not having seen a particular app on other devices means nothing (to me the name "Saffron" would make me think of a theme, but that may be completely wrong). More surprising is that your settings are showing an app that appears to have no data usage.