I don't see why everyone is calling him dense. To him, they are just children he has to take care of.
He just doesn't really care about them outside of those parameters . They're a means to an end, that end being returning home.
I'm sure as it goes on, if it goes on for that long, he'll slowly start to soften up to them and eventually come to love and cherish his- what was it? 10 girls he has to raise?
Or he won't and he'll stay apathetic the whole time. Who knows!