Interesting concept, just feel like "killing the pet" (feels weird even saying that ahaha) could've been more fun. Also, the end boss felt a bit spammy, I had to keep mashing Z/X non stop to shoot as much as I could, and I managed to cheese it by staying at bottom right where neither the knifes nor the projectlies could hit me.
Nonetheless, a concept I didn't expect to see anywhere, presented in a decent manner.
Goodjob!