I despised him at first then realised I actually would probably be even worse. He was trying to help mother and daughter and had no reason at time to believe he special...though the zombies bashing at door were a big give away. That scene was actually significant when you look back because that horror and guilt was when he suppressed his emotions and become so emotionally detached (which was his way of dealing with things just as he did when he lost job, he shut down emotionally and kept busy playing games for a week straight and even then he was still very emotionally detached). Everything became coldly logical practicality even the pointless busy work keeping himself busy cleaning out way more stores of rotting perishables than he ever possibly need even though he knew the city only ever be temporary and dependent on power staying on. Though I only really picked this up in hindsight when we first switched perspectives and saw MC from her perspective. The character is bloody well written and you see the emotions are slowly coming back by end of this chapter.
Ehhh, I kinda disagree.
He's a strange character. I at first thought he was just a sociopath who cannot handle people unless he enters contracts with them, which he does for all three heroines, but really I think he's just someone who hates people to the point where he's just lost empathy. He's a very lawful evil protagonist.
The reason I disagree with your hypothesis is because he doesn't reference the mother and daughter once, and the narrative is mostly from his point of view, meaning he could very easily delve into a interior monologue about it whenever he wanted. He does that for many other things, after all.
There is also point in Chapter Two where he feels real guilt towards the events at the end of Chapter One, even though logically and practically what happened there was a lot tamer than what happened with the mother and child. Why? Because he failed to meet the requirements of a contract he made with Mitsuki, although it is definitely likely that he does feel some sort of love for her too.
But that scene also brings the mother and daughter scene into question. He didn't pick up on the fact that zombies don't attack him despite the huge hint, although I guess we can kinda forgive this since society has literally collapsed and he's just woken up from a several week long recovery. But even so, he still offered to take them to shelter, and failed to protect them. It was absolutely his fault. So isn't that also failing a contract? Maybe he doesn't feel that way because he was gaining nothing from taking them, meaning he was really the only one putting in any work. I dunno.
He definitely still has some basic morality. He feels as if mistreating zombies to the point of mutilating them is wrong, he doesn't like the idea of killing another human (although it seems he overcame that), and he believes that he shouldn't unnecessarily cause trouble for other people, which was established when he admonished the dead humans at the university for doing the same when they created intelligent zombies.
Nonetheless, it's pretty well written. I'm surprised how little backstory we have of the dude, we only get a little bit during Chapter One when he's watching one of the kids play and that reminds him of waiting for his grandpa. I think neglect is probably a huge factor to his character. I may replay it.