Shun has presumably known his senior, Isshiki Satoshi better than anyone else as he was stayed much longer than the rest of the Polar Star Gang.
Unlike his passionate room mates, Shun is very realistic on the terms and very serious upon making his style in perfection. Shun is also a quiet student who prefer speak only whenever is considered as crucial by many. It is also once claimed that he is a calculative chef whose choose to act wisely over hesitation.
(Source: Shokugeki no Souma Wikia)