This means - two or more MALES. No females, no dickgirls.
For any heterosexual - id est, male / non-male - incestual interactions only 'mixed:incest' should be applied, and only non-male participants tagged.
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Tag "male:incest" means there is a scene of ONLY MALE RELATIVES involved in incestual interaction. No females, no dickgirls.
Tag "female:incest" means there is a scene of ONLY FEMALE/DICKGIRL RELATIVES involved in incestual interaction. No males whatsoever.
For ANY form of heterosexual incestual interaction - id est, involving at least one male, and at least one non-male - only "mixed:incest" should be used, and only non-male participants tagged.
https://ehwiki.org/wiki/incest
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Tag 'story arc'
>Requires a minimum of ~75 pages or 4 chapters, whichever comes first, within a single gallery.