Scenario break by the weakest mob starting with hard work, knowledge and perseverance – Gamer reincarnated as a mob in a game he has been playing, sur

Arcadia Quest, a popular game with a storyline that branches into more than 100 different routes and attractive characters, just one character, Crescencia, has a tragic fate in every route. The protagonist of this game is a NEET gamer who loves Cresencia. He spent day and night playing Arcadia Quest in order to find a route to save Cresencia. However, no matter how many years passed, he could not find such a route... and that day, he made one more failure and went to sleep.
And when he woke up the next morning, to his surprise, he had been reborn in the world of Arcadia Quest! The protagonist was happy that he could now save Crescencia with his own hands, but his new life was as a mob character, no better than a useless dog. Naturally, he is not strong. To put it bluntly, he is a small fry .
But the hero was not discouraged. If I am a small fry, why don't i train? If I don't have talent, why don't to train? If saving Crescencia it's too difficult, why not train?
It's all for the sake of the favorite character . The lack of talent is compensated with a cheat -like effort, and the mob characters are outclassed with a vigor that change the storyline.