Shuichi appears to have quite a serious and polite personality. However, he is also stated to have a weak personality, and he is abnormally timid when it comes to speaking. He often has negative remarks, frequently blushes and suffers from a cold sweat. With his unsure demeanor, he has a tendency to assume that other people can do things better than him, and he comes across as quite unreliable at first glance. Among the sixteen students, he is a boy who stands out for his submissiveness but also for his level-headedness.

Here are some voice examples: https://youtu.be/MfhIj8eIRNU