Yoshimasa Hosoya

Yoshimasa Hosoya and the Weight of Reiner Braun

Few seiyuu careers are defined by a single character the way Yoshimasa Hosoya’s has been shaped by Reiner Braun. From the first season of Attack on Titan in 2013 through the sprawling Final Season, Hosoya carried one of anime’s most psychologically fractured soldiers – a man split between identity, loyalty, and self-destruction. The performance demanded something beyond technique. Hosoya’s baritone could project Reiner’s warrior facade and simultaneously let the cracks show underneath, giving the character an anguish that made him one of the most discussed figures in the franchise’s history. Born February 10, 1982, in Onomichi, Hiroshima Prefecture, Hosoya was drawn to voice acting after watching the character Hokushin in the Nadesico film – voiced by his idol Koichi Yamadera – and deciding he wanted to inhabit characters the same way. He graduated from Tokyo Announce Gakuin Performing Arts College and entered Mausu Promotion’s actor training center in 2002, turning professional around 2004-2005.

Sports Anime, Seiyu Awards, and a Career Built on Range

Hosoya’s breakout came earlier than Attack on Titan, with the 2007 Prince of Tennis OVA series establishing him as a recognizable voice. What followed was a steady accumulation of major sports anime credits – Junpei Hyuga in Kuroko’s Basketball, Sosuke Yamazaki in Free! Eternal Summer, Asahi Azumane across all four seasons of Haikyu!! – roles that showcased a register both warmly grounded and capable of sudden intensity. The industry recognized this depth. Hosoya won Best Supporting Actor at the 8th Seiyu Awards in 2014 and again at the 10th Seiyu Awards in 2016, a repeat achievement that placed him among the top tier of working seiyuu. In 2017, a throat condition forced a four-month medical hiatus. He returned without missing a core credit, resuming Reiner Braun and picking up new work immediately. The experience led him to leave Mausu Promotion for freelance status – a transition that, far from slowing him, opened his schedule to an even wider range of projects.

Nicholas D. Wolfwood and the Trigun Stampede Chapter

When Studio Orange reimagined Trigun as Trigun Stampede in 2023, the casting of Nicholas D. Wolfwood required a voice that could match the show’s harder, more melancholic tone. Hosoya stepped into the role – previously held by Show Hayami in the original series – and made it entirely his own. His Wolfwood carried the weight of a man who knows his purpose and despises it, each line delivered with a low-register gravity that matched the show’s visual aesthetic. The performance brought Hosoya renewed international visibility and extended his reputation as the seiyuu best suited to men who carry impossible burdens with quiet intensity.

From Demon Slayer to New York Comic Con

The years since have kept Hosoya working at the highest level of the industry. He appeared in Demon Slayer: Kimetsu no Yaiba – Infinity Castle in 2025, the theatrical continuation of one of anime’s biggest franchises. That same year he appeared at New York Comic Con for a signing event and Gundam panel alongside director Tatsuyuki Nagai – a marker of the international profile he has built across two decades. Away from the booth, Hosoya has also narrated documentaries, dubbed Western productions including The Sandman for Netflix, and debuted in live stage performance in the 2023 comedic play Harvey. In March 2025, he announced his marriage to a non-industry partner. His official YouTube channel, Boku World, offers fans direct access to his life outside the recording booth – a rare window from a seiyuu who spent years resisting social media entirely before finally joining X in 2021.