These are the crab guys! The frigid seas surrounding Hokkaidō are bountiful and yield some of the tastiest crustaceans around. Try the kani-suki (¥4600 per person), a crab version of sukiyaki; after the crab and vegetables are cooked in the pot, rice and egg are added to the remaining soup.
You can't miss it: there's a huge crab sign on the building. There's also a branch near Susukino crossing.