Yamada is a reserved and introverted individual, much like his mother who also shares the same shy demeanor. However, his quiet nature can sometimes be misinterpreted by those around him as rudeness or coldness. This is because he tends to keep to himself and doesn't always express himself openly. Despite this, Yamada is actually an extremely helpful person who goes out of his way to fulfill promises he's made to specific individuals. He's willing to exhaust himself if it means keeping his word