Looking for a hentai. It was only one chapter as far as I know. It was about a father and his son going to the hot springs with step mother and her daughter. Once there it became an orgy between them. Don't remember name/artist. Any help would be welcome. Here are some Futa pics as a bribe.
[Satsuki Imonet] Step Child Swapping (COMIC Tenma 2014-12) [English] {Striborg}
https://exhentai.org/g/880064/9516739859/
Pretty solid doujin
>>6962145
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