Kei will probably like kids. Enough to hang around despite how distrustful he is of generally everyone. 

By the way, for the mysterious benefactor of Kei I mentioned before, I don't mind if he's included in a minor/major/relevant part of the story. I prefer that said benefactor won't be evil, but... (In fact, I think his benefactor will be the only reason Kei comes to Fu Sonzai no Genso. Namely, him leaving Kei a note telling him to 'get a job!')

/shrugs.