The inverted Marrissaverse is an alternate universe in ASBusinessMagnet's MarissaTheWriter stories. Characters who die in the inverted Marrissaverse appear in the "main" Marrissaverse in the same way characters who die in the main Marrissaverse appear in Andord Hell. It might appear that Meanie Pixies is an exception, as she appeared in the dream bubbles after dying in the inverted Marrissaverse. However, this is actually a direct consequence of her sharing bodies with Janet Roberts.
The name "inverted Marrissaverse" does not appear in any MarissaTheWriter story. Instead, it is taken from ASBusinessMagnet's piece of fanart, MarrissaTheWriter Family Tree v3.2.0 (now removed from the Internet).
Like with Andord Hell, there is no clear beginning point for the inverted Marrissaverse.
Post-SCrash Session 2: The Belorussian Aliens is mostly set in the inverted Marrissaverse, and tells the story of one of its planets, Belarus. It is home to various aliens with candy corn horns and gray skin, twelve of which, including Meanie Pixies and Aranna Sorket, escape to Belarus's pink moon. Eventually, they destroy Belarus and kill themselves.
- MarrissaTheWriter Family Tree purports that Altair is not situated in the inverted Marrissaverse. However, this has been discredited by Meanie Pixies' Hour of Fame, which shows that Altair is Belarus after its destruction and reconstruction.