Everyone loves an underdog.
A story is boring when you’re protagonist always has the upper hand. We’d rather root for someone with the odds stacked against them. Because we often see ourselves in them. We can’t help but root for them to succeed because they’re faced with impossible odds and refuse to give up.
My Hero Academia has plenty of underdogs. Deku, our primary protagonist, has been one since episode one. A little Quirkless boy trying his best to become a hero. Surely that’s the most engaging thing in the story, right?
Well, no. Because this kid exists.
When he was first introduced, Shinso was an antagonist. He acted entirely hostile towards Deku and the others. He freely used his powers to manipulate others in order to achieve his aims. While he was never as sinister as Shigaraki and the League of Villains, he certainly didn’t seem like a very good kid.
Which was entirely intentional. A big aspect of Shinso’s character is, in a roundabout way, villainy. His Quirk lets him mind control people so long as they respond to him. He even looks somewhat villainous, with his sickly pale skin and dark rings under his purple eyes. Combine those two things and he could very easily be a villain in the story. In his backstory, it’s revealed that people have been telling him that for years.
But Shinso isn’t that kind of kid. He’s just like all the others in the series. Noble, selfless, ambitious. He can see how useful his power would be in hero work. The kid could be a one-man solution to a hostage situation or any number of potentially dangerous situations. His Quirk could save more lives than any other in the show.
This is where Shinso stands out. See, he doesn’t struggle to defeat powerful foes. He struggles against something all the more difficult to overcome: society’s standard for heroes.
From what we’ve seen, the world of MHA values strength in its heroes more than anything else. Heroes need to be strong, need to be quick, need to be dependable. So schools like UA primarily test for physical capability for their hero course. If you can’t smash enough robots, you don’t get to be in the hero course.
This is the center of Deku’s underdog story. The little Quirkless boy is given a power he can’t control and needs to find a way to use it in order to keep up. His primary struggle is to get stronger. His body needs to keep up with his heroic spirit.
But as soon as Deku had a Quirk, he gained the means to overcome that wall. Something that Shinso doesn’t have.
Shinso’s Quirk doesn’t help him smash robots or beat up villains. It’s practical in an entirely different, arguably better, way. But because of how the world thinks heroes should be, the door is slammed shut in the boy’s face. Now, he needs to find a way to open it.
That’s what makes Shinso such a compelling character. The door that Deku had opened for him, he needs to find a way to open himself. He’s had help, sure. But he’s not being handed some magic key. He’s stuck with what he has and needs to find a way to make it work.
Whether he’ll get the screen time to do it or not is another matter entirely.