When you first meet the rabbits, at first you feel sympathy for their situation, and think the protagonist is a jerk for mistreating them, until you begin to understand that the rabbits are totally insane and beyond help, and the guy's behavior, cruel as it is, is pretty reasonable in context. This frees you up to enjoy the chaos.
They'll literally die if they stop working for more than a few minutes (it's like a curse or something, the curse of mochi). The rabbits are highly intelligent and competent, but have the wisdom of a hive insect, and zero survival instinct. It borders on psychological horror sometimes. (There's a Junji Ito reference at one point.)
Perversely, the artstyle has a very moe quality. I couldn't help falling in love with those weird rabbits. They're so cute. I want them to win, and be happy. I think that's what really pulls the manga together.
