This creates a psychological split:

Indonesian society is predominantly collectivist. An individual’s behavior is not just their own business; it reflects on the family, the kampung (village), and the religious community. Acts considered "mesum" are viewed as disruptive to social order. Premarital sex, adultery, and unconventional sexual acts are taboos enforced not just by law (via the KUHP or recent anti-adultery articles) but by neighbors and family pressure.

Since the early 2000s, Indonesia has had strict censorship laws. While local film and television industries are heavily regulated, Japan’s adult video (AV) industry historically produced content that was easily accessible, technologically advanced, and—crucially—heavily fetishized.

Specifically regarding , Law No. 44 of 2008 on Pornography makes it illegal to produce, distribute, or use pornographic material. Technically, an Indonesian citizen caught streaming "Mesum Jepang" could face prosecution, though enforcement is usually aimed at distributors.

In the digital age, language evolves rapidly. Among Indonesian netizens, particularly the younger generation, a new colloquial term has surfaced with surprising frequency:

For the average Indonesian browsing early internet cafes (warning), "Jepang" became synonymous with a specific genre of hardcore content that was perceived as more extreme than Western pornography. Terms like JAV (Japan Adult Video) entered the local lexicon. Consequently, "Mesum Jepang" evolved as a catch-all descriptor for any highly explicit or "kinky" behavior that deviates from the conservative norma susila (decency norms) of Indonesia. To understand the outrage, one must understand the Indonesian concept of Malu (shame) and Rukun (social harmony).