The MC is right that if Ares know of the the MC’s skill, he would stop fighting. If you’re asking why?
Because of Automated debuff. Ares would see that, put the MC in the frontline, and have his skill be automatically activate, and let’s remember what
Automated Debuff does, it weakens you body to such an extreme that your body can’t handle it, and begins shutting down, it also can blind you, take your hearing, it will do anything and everything to take your life if you don’t surrender.
In Laymans term it can and will kill you if you are an enemy against the MC the only way to life is to surrender.
Ares would see that put the MC in the front lines would see how weak the enemy gets, then take the kill and take all the credit while acting as if he did everything, and everyone would believe him because he’s the hero. Why would the hero lie? And let’s not forget that a lot of people don’t know that the MC is a….. I think it was a triple S rank hunter, very minimum S rank.
MOST people would just see him and know him as the porter. No one would know it was really him, unless they knew him. So who would the people believe the hero who is going to kill the demon lord or the MC who is the porter.
So I think the MC is valid in not telling Ares his skill.