Snake Eyes is an inanimate object that only appears in the episode "Bubble Buddy."
Snake Eyes is merely two fuzzy pink dice with the one side up.
Role in episode
It appears when the citizens of Bikini Bottom are about to pop Bubble Buddy. SpongeBob tells the people that Bubble Buddy is his friend and asks the town if they have ever had a close friend. From there, citizens start bringing up material possessions that they consider friends, one of which is Snake Eyes owned by an unnamed fish.