Responses
the guy next to 704 is just another reaper. We see him with yama http://www.mangago.zone/read-manga/fate_makes_no_mistakes/nto/ibx_chapter-53/pg-1/
He's probably scared either cos he's in a room full of scary/powerfull people OR they just found out San is actually human, and they made a mistake.
Who was the guy standing beside 704 at the end of the chapter ?