@TsunKingFenris
He didn't say he didn't want to be a hero, he was honestly just too realistic and pragmatic about it all when they were first summoned.
The others followed the isekai trope
*Summoned from everyone else other than their fellows summoneds*
*Immediately agrees to help whoever summoned them without any reparations or guarantees other than verbal promises they don't know whether the people giving them are honorable*
He was more 'Explain the situation in detail.'
*Didn't get good explanations, was about to be thrown out had a discussion with the student prez*
*Rejected the stuco prez's offer of saying and if necessary actually taking over the world if they don't like how the situation changes*
Basically, he was too rational to follow their idiocy and just wanted to leave.