Tooru Hoshina

Age: 18 Member of Yamato's security division. Rank: Warrant Officer. A Tokyo native. A member of the security division who puts all his trust in Ito. A handsome, sociable young man who always wears a smile.

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It was later reveled that he secretly works for the Strategic Planning, Division 6, whose task was to investigate member of the Izumo Plan backers who had infiltrated on board the Yamato. He was able to quell the mutiny with help from Shima and Sado.

(Source: ourstarblazers.com)