also did gravure modeling; as a result, the demand for newer talents was reduced. : Since the 1970s, several voice actors of anime and video games also held successful singing careers in addition to voice acting. Early examples of voice actors who had an idol-like presence were Mobile Suit Gundam voice actors Toshio Furukawa and Toru Furuya in the 1970s, who gained a sizeable female following after forming their band, Slapstick. In the 1980s, idol singer Noriko Hidaka eventually became a voice actress after gaining recognition for playing lead in Touch. Beginning in the 1990s, several voice actors held successful concurrent singing careers alongside of voice acting, such as Hekiru Shiina, Mariko Kouda, and Megumi Hayashibara. As the anime industry began producing more late-night series in the 2000s, the term "idol voice actor" was popularized when more voice actors with a cultivated fan following began appearing on television. While previous examples involved voice actors who incidentally drew in fans through their singing careers or former idol singers who turned to voice acting, Yui Horie, Yukari Tamura, and Nana Mizuki were intentionally produced and marketed as idol voice actors by their record labels. Around the time when the Idol Warring Period was occurring during the mid-to-late 2000s, there was a significant boom in idols voice acting in anime, with Oricon naming Aya Hirano and Koharu Kusumi as examples, as both of them were established actresses and singers in mainstream Japanese entertainment before entering voice acting. Hirano, in particular, was strongly marketed as an idol at the height of her voice acting career, from the late 2000s to the early 2010s. While character song tie-ins were already common in the film industry by then, some voice actors also began making crossover television, stage, and concert appearances as their characters as well, leading them to be closely associated with one another. : While Japan and South Korea agencies have created collaborative idol groups in the past, with Route 0 in 2002, during the third Korean wave in the mid-to-late 2010s, the term saw usage again to refer to collaborative idol groups promoting primarily in Japan, but with music, styling, marketing, and presentation produced in the K-pop industry. The earliest example is Iz*One in 2018, followed by JO1 in 2019 and NiziU in 2020. : Male idols contracted to Johnny & Associates are nicknamed "Johnny's idols" by the media and include groups such as