There are characters in the public domain that happen to wear diapers, like this Jerry-looking guy. His name is Marmaduke Mouse, and he’s from an obscure comic series from the 1940s. A bit more info here: https://imgur.com/gallery/marmaduke-mouse-2RknrAJ
FWI, I first learned of Marmaduke Mouse from this (as of posting this) ongoing comic by
KelvinTheLion: https://www.furaffinity.net/gallery/kelvinthelion/folder/1349961/Marmaduke-X-Superkatt/More info:
https://www.toonopedia.com/marmadkm.htm (Don Markstein’s Toonpedia)
https://dc.fandom.com/wiki/Marmaduke_Mouse_Vol_1 (DC Database)
https://pdsh.fandom.com/wiki/Marmaduke_Mouse (Public Domain Super Heroes)
https://comicbookplus.com/?cid=890 (Comic Books Plus – Hit Comics)
https://comicbookplus.com/?cid=1318 (Comic Books Plus – Marmaduke Mouse)
– CyberDiaperMan
A series of images drawn by EndoudouhuRau and commissioned by CyberDiaperMan.
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CyberDiaperMan
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