>>2582650A doujinshi of Amagi Brilliant Park called Brilliant na Usui Hon by the artist for the source material, Nakajima Yuka, so official Sento nipples.
https://amaburi.fandom.com/wiki/Brilliant_na_Usui_HonI haven't seen the book scanned in Japanese, but from reading the sample images on mandarake, I can tell that they want to save their park by having a boob groping event, where everyone can come in, pay 1000 yen (10 dollars), and grope their tits, in reference to this charity event:
https://www.huffpost.com/entry/boob-aid-charity-breast-squeeze_n_5791512?slideshow=true#gallery/5bad8b24e4b04b2386d0cc29/10The fact that this is semi-official makes it even hotter.
