Unable to answer "What type of bicycle rental is this?" – 千歳橋 (Bicycle Rental) – https://osm.org/node/12307136551 via StreetComplete_ee 63.0:

The area looks overgrown, so at least there hasnt been a bike rental here in a while.
Unless it is supposed to be inside? But i didnt see the building open today

Attached photo(s):
https://streetcomplete.app/p/339869.jpg