Why is this listed separately from
https://mangadex.org/chapter/21fccc4b-88f0-4ab5-91d6-a059d358f243 ?
It's a three page long story, there's no need to break it up.
"Ah, but this part was posted on twitter, but the porn bit is only on fanbox!" So? it's a two page long lead-in/ advertisement for the porn. Why the fuck would you spread 3 pages of story across two whole manga listings? Honestly, I think twitter comics like this should all be grouped together per author. In fact, this is sometimes done on this website, see:
https://mangadex.org/title/366dcef2-11ac-4ec0-9d75-967638f211a7/holiday-yasumi-s-twitter-shorts Also, when an ecchi comic gets an extra chapter that's published on pixiv or something, that still gets listed with the rest of the chapters even if it's more ecplicit than the main story.
I don't get why the convention on this website is so inconsistent.