In the episode, Louise comes down with the flu and has a Wizard of Oz-esque fever dream involving a disfigured Kuchi Kopi and her toys, who have the voices of her family.
Tina claims that the oven will make it dry faster but Bob accidentally leaves it in too long causing it to melt, Gene then attempts to fix it only to disfigure it.
("Not the Forgiving Type") She then has a fever dream in which she is in a fantasy world with her current Kuchi Kopi (Now named "Ugly Kochi Kopi") who takes her on a journey to the "Impenetrable Fortress" a place where she can be alone while several of her other toys (representing her family) attempt to stop her ("That Fortress is the Worstest") while Ugly Kuchi Kopi claims that they are simply jealous of not being invited as Louise makes it to the fortress and quickly shuts out the toys and is relieved about being alone.
Club gave the episode an A−, saying, "“Flu-ouise” could have hit its themes and character beats harder in its fantasy sequences, but that would have likely meant drawing even closer visual parallels between the toys and Louise’s family, or using their actions as more obvious allegories for Louise’s frustrations with their failures.
It’s not as tightly focused on Louise learning a specific lesson or working through her issues as it could have been, which—whatever weaknesses that might entail—does mean the episode can throw in delightful, generally Belcher-like character bits like the bear building a sun deck to relax, the octopus drinking heavily with all her pals, and the two final toys trying and adorably failing to be threatening.