Yumemiposter here. By pure chance, I stumbled across the origin of how she ended up getting so much ringo art while searching for ringo art that wasn't chuuba related. A tweet she made back in February about how she had a dream about peeing on the balcony during a stream because she couldn't hold it anymore.
https://twitter.com/Kumonoue_Yumemi/status/1488401685580238848It seems like one fan who really likes pee commissioned a bunch of different artists to draw her doing it in various situations. He also clips pretty much any time pee comes up on her streams
https://twitter.com/techno_neetI feel weird shilling this much for a chuuba I barely watch, but something about a card game player who engages in lolidom in her spare time just does it for me 