Yuzaki Nasa
Nasa's full introduction says it all: "My name is Yuzaki Nasa!! The man who'll attain the speed of light faster than NASA!!" It's a pretty on-brand way to sum up his whole personality.
Growing up with that name wasn't easy. Kids bullied him for it, which honestly makes sense—it's unusual, memorable, the kind of thing that invites jokes. But instead of just accepting the mockery, Nasa decided early on that he'd make people respect his name rather than laugh at it. His solution? Work harder than everyone else. And to his credit, he mostly pulls it off.
His life changes dramatically when Tsukasa saves him in chapter 1, and he ends up marrying her shortly after. It's a pretty unconventional start to a relationship, but Nasa turns out to be genuinely invested in being a good partner to her—even if he does have a somewhat perverted streak that occasionally shows through.
One thing fans often note about Nasa is how obsessively organized he is. He's mentioned multiple times that even if his entire house burned down tomorrow, he'd be completely fine, since he keeps nearly everything either digitized or cheap enough to replace. It's the kind of detail that says a lot about how his mind works.
Content compiled by AnimeList.moe from publicly available sources.