In the anime and light novel series Re:Zero - Starting Life in Another World, Subaru Natsuki (voiced by Koboyashi Yuusuke or Sean Chiplock) is the main protagonist.  Subaru is transported from a convenience store in Japan to a fantasy world where he becomes a knight to the half-elf Emilia.  Subaru typically wears the tracksuit he had on when he was brought to this new world, however he also has a butler's uniform he wears while serving at the Roswaal mansion.  A standard butler's costume will help to achieve this look, especially if you take the time to carefully outline the lapels with some standard grey fabric paint.  If you don't like the look of a multi-striped bow tie, you could also use a plain blue one and paint a single stripe across it once it is tied.

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