Just watching the face hopping around on the display gives me oldschool Tamagotchi vibes. Imagine you’d wire up some ‘personality and need functions’.
More or less a few timers that are set within a certain randomness - so after some munching it digests those and the results are dumped so you’d have to flush it. A very simple minigame could just boost its mood and some other small stuff.
Side effect: You wouldn’t have to walk around yourself as a kid will gladly take over and carry it around in a much larger environment as kids do.
attention: This post may contain traces of black humor, sarcasm and/or irony.