Burt Buddy by KDOG is a short little Tamagotchi based game made for Nintendo Game Boy.
In this game, you play with Burt to keep him happy. If you start to leave, he will tell you that he will be left all alone and as to keep you occupied, he will give you options. First, you’ll feed him food then you will play a mini game and continue on. While you do that, he will sstart growing.