The list of unknowns regarding the resident crystal giant is long enough not to bother thinking about it, and instead, focus on the known facts:

Bob is quite large. Bob does not speak. Bob can tear down a building. Bob protects Clyde. Clyde keeps Bob from tearing down buildings. Bob is Bob.

Despite his intimidating presence, Bob is usually rather docile. But the mere possibility of what damage he could single-handedly do, or worse, with the support of Lily and Clyde, is enough to make Bob the perfect trump card for Clyde to get away with pretty much any stunt, because it could be much, much worse if he doesn’t.

The glittering armor covering Bob is suspected to be Bob’s Electi ability, composed of unique biological emerald-like crystals that are able to protect Bob from most harm. The suit of armor anomosly moves as the rocks themselves were bones and muscles, leaving the answer of whether this Electi is more rock than human to the very few individuals who had seen the truth beneath the armor.

Bob additionally can “corrupt” other minerals, turning them into the Bob-crystals and enabling control of those externally in addition to his armor, however that leaves him unable to move his body at all, as he must relegate all of his Electi ability’s capabilites to just move.