what did "otaku" mean in 1993 in the UK?

I am once again wondering about cultural context that I don't have. into the rabbit hole we go.
thanks ‪@kennylauderdale_en‬ for giving this script a once-over
the background music is, of course, "Otaku" by the Black Dog (albeit arranged by me)
available here: soundsfromsci....
The subtitles have a few citations:
[1] Fandom Unbound: Otaku Culture in a Connected World, page 85
[2] groups.google....
[3] web.archive.or...
[4] banbantonton.c...
[5] thequietus.com...
[6] music.ishkur.c...
Here's the kinda-favorite-songs list I mentioned, sans a few songs that aren't on youtube:
• Foundational Music tha...
it's a little silly and eclectic, though, so beware!