Hiding identities was too bothersome for Seishirō Nagi, that's why Reo was the first to find out about his powers. He was the one to convince Nagi to become a hero. "Go for it", Reo pressed over and over. He said it would make his life more interesting, and promised Nagi he'd take care of all the hard technical stuff, as long as he just shot his shot. He wouldn't know if he hated it if he never tried.

So he did (reluctantly), and Spider-Man was born.

It isn't worth the hassle. The same thought drifted into Nagi's mind. Why did he have to worry about hiding his face on top of fighting and saving people? It sounded like extra work to him, but Reo insisted it had to remain a secret so he did his best... Which was the bare minimum: wearing a mask when fighting.

Nagi didn't think much of it when he told you. You simply commented, wondering who Spider-Man was, and he responded. "Oh, it's me." In the most casual and uninterested tone ever.