Right after this series, the teenager was offered his first starring role in a movie, as the meekly salesman Tibe-kun, who tries to deal with the yaoi passion of his girlfriend in the comedy Tonari no Yaoi-chan, a self-parody movie based on a real-life blog that centered on the 801-chan phenomenon. Manga artist Tateno created the character design originally based upon the actors - a very rare occurrence. The drama followed Makoto Tateno's script, which was published alongside the TV series in Manga-form. He starred in his first leading part in spring 2007, as the dallying greenhorn Kyoichi Segawa, a young gentleman Butler in Happy Boys. This way, he was able to act out his part in eight different ways.
Seto was not just a boy in an old-fashioned green uniform - he also had the ability to change his persona with the use of his 'Miracle Glasses'. He co-hosted the show constantly from then, once a week together with Kōichi Yamadera, until his graduation on April 28, 2008. In late 2006 the young actor was chosen as Thursday's-face of OhaStar, a children's TV show airing live every morning on TV Tokyo. Seto's official D-Boys logo is a chameleon, in reference to his versatility.
