There is a lot of good food in Japan - essentially places that mainly locals go and Sasagin would be one such neighbourhood izakaya. Izakaya, in my mind, are like pubs or tapas bars where the focus is on the drinks and generally decent food happens to be served as an accompaniment. In Sasagin's case, the food is also excellent while sake is the owner's forte.
A Japanese foodie friend recommended we come to Sasagin - good food without having to pay a lot for it. While not much english...