Hoi Hoi

Dead animals can also enter the Gantz room. The first animal seen in the Gantz room was a dog Butter Dog. Hoi Hoi the panda entered the room a while after the dog got killed in the Buddha arc like every other character save Kurono. Hoi Hoi is especially fond of Izumi and can be seen hugging him whenever a chance presents itself. Like the butter dog in the two missions before he was crushed in the anime who hadnt gained a single point by then it will be difficult for animals who enter the Gantz game to survive or even clear it. It is assumed that most animals who enter the game usually die when wandering around and eventually leaving the selected location and have their heads blown up. wikipedia