It's a seeecret.
![tatara kogasa and kyubey (touhou and 1 more) drawn by mizuki_hitoshi](/cdn_image/original/f5/8d/__tatara_kogasa_and_kyubey_touhou_and_1_more_drawn_by_mizuki_hitoshi__f58defd94395f9e004d6b56d1024ea52.jpg)
Artist's commentary
Hang in There, Kogasa-san 2771
In fact, I was told about these by a famous author of a Kan-Colle-related pilgrimage gourmet book, but that explanation looked like it would become circuitous, so went with QB-san. :-) QB-san actually did appear to be using it, though.
I asked the Benben-san person about the matter of abandoned bicycles, and apparently, it is becoming a problem in Taiwan after all. It was one of those, "Yeah, that sounds right" moments.