I don't really keep track of other community sites as reddit, so no idea if someone already went over the bits of Japanese text on the pic but...
so first off, the Japanese name for this content is クロの空想帳, which you can translate into "Kuro's book of fantasy/daydreams"
Also the way too blurry text in the gray box seems to be about reseting those stamps, and it mentions the name クロ・アリアポー, which can be read as something amongst the lines of "Kuro Ariapoh or Aliapoh"
Looks like that's the actual name for our Cinnamon Roll. A keeper name, huh
Plus the rewards that can be seen are for "completing (filing) 9 squares" and "1 line"