Isekai is Here! Genres/Themes Overhaul Part 1.5

Experimental fiction which shunned conventional storytelling at the time it was created. These stories often invoke unsettled feelings because they reject traditional ways in which we prefer to view (or escape from) the world. Narrative is avant garde works is often of higher importance than the content.

Character traits (e.g. magician vs demon/spirit) and setting do not determine if a story is Fantasy. If majority of the cast has magical or supernatural powers (e.g. one normal highschool boy surrounded by five goddesses), then the story is Fantasy. If only a few characters have powers and most of the cast would be in disbelief to discover this (e.g. one man is an exorcist and the rest are normal adults), then the story is Supernatural. Sometimes a story can be both Fantasy and Supernatural, but this is rare.

Show business, or Showbiz for short, describes the industry which produces popular entertainment media such as television shows, movies, radio programs, magazines, and mainstream contemporary music. One or main characters in Showbiz themed stories work in the entertainment industry, either as a performer (e.g. actress, model) or in business development (e.g. manager, producer). Their occupation should also be central to the main story's plotline. For example, simply dating a famous band member but never seeing that character perform or struggle with their profession is not Showbiz.
Idols-themed stories are a subcategory of Showbiz, so they are not double-tagged with Idols (female) or Idols (male). Stories featuring a main cast of both female and male idols equally is rare, so those will be have the Showbiz theme.

Slice of Life stories are focused on a seemingly random and mundane period of the main characters' lives. The absence of a central plot to carry the story towards a charted destination means Slice of Life stories frequently lack overarching conflict and resolution. While life is not without conflict and Slice of Life neither, here conflict appears and dissipates seemingly at will, without a specific narrative to enforce it.

Slow story pacing or episodic storytelling does not equal Slice of Life. Drama/Romance stories can be slow and soft while maintaining a central plot of human/relationship struggle. Comedy stories may lack progress and have mundane settings, but they have narratives focused on eliciting laughter rather than amusing moments happening naturally. Thus, Slice of Life is incompatible with Comedy, Drama, and Romance by definition.

Instilling a sense of anticipation and excitement takes priority, and is accomplished with a narrative that is rife with twists, turns, and red herrings. Uncertainty is present every step of the way, often drawn out for maximum effect. A variety of tools are used to keep the audience on the edge of their seats, such as withholding important information, intentional misdirection, or even outright subversion of expectations.
Suspenseful moments do not mean a work is Suspense; the feeling of anticipation or anxiety must be maintained throughout the story. Contrast with Horror where the audience is in a constant state of apprehension and dreads the next event, rather than craving it. While Mystery also instills anticipation, the tension is focused on discovering the solution to a puzzle, rather than knowing what the characters will do next. Sometimes a story can mix Suspense with Horror or Mystery, but this is rare.

A theme within the Mystery genre, these stories feature either a detective or amateur investigator working to solve a crime or puzzling event. To classify as Detective, the character must either by employed as an investigator (e.g. police officer, private detective) or be sought out by enforcement/clients because of their case-solving reputation (e.g. Sherlock). If the character only seeks out mysteries as a hobby or becomes embroiled in them randomly, then the Detective theme does not apply. Anti-heroes being pursued by enforcement is not Detective.