I'd heard Kumoko was an unofficial name for the protagonist of So I'm a Spider, so What?, so I didn't expect to actually encounter it in either the light novels but it's there. In Yen Press's translation of the first volume, it appears on pages 199 and 200, in Chapter 11: Still Clearing the Lower Stratum :
I mean, if I learned how to use these, I would basically be a magical girl... Well, a magical spider, anyway. Like "Kumoko the Spider Girl" or something.
Damn. It looks like I won't be able to call myself Magical Girl Kumoko for a while yet.
The name also appears in the ending songs of the anime. If this is an unofficial name, it seems it's been adopted. Do the original light novels really have something different in place of this text and never use the name? Or is the name merely considered unofficial because Kumoko's name appears as "nameless" when she Appraises herself?