And to this day, I still don't know what's the connection between Kana and road signs...

PrincessBlackRose said:

And to this day, I still don't know what's the connection between Kana and road signs...

6 years late comment
The reason why many fans draw Kana with a road sign is because ZUN mentioned it in their old blog, specifically in the MIDI music download section.
When opening the text file, the one who comes included with the song can read the following
The concept for Kana's image (which I would always write down before designing the character ^^;;) was "a Western-style girl holding a damaged road sign behind her back".

TLDR: Basically, Kana's early designs, she was holding a road sign which ZUN then removed later, fans loved the idea and have since drawn him holding one.
exactly the same thing happened years later with Okina in her wheelchair

tremolo_measure said:

6 years late comment

TLDR: Basically, Kana's early designs, she was holding a road sign which ZUN then removed later, fans loved the idea and have since drawn him holding one.
exactly the same thing happened years later with Okina in her wheelchair

Okina's wheelchair is canon though, it appears in official materials, not just early designs and concept art.