Kushi Bar is a Japanese bar/ restaurant chain with a fantastic menu of Japanese food, specifically seafood and barbecued meat. This Taipei bar is situated in a busy but quiet alley in the Daan district behind Sogo and between Fuxing, Dunhua and Zhongxia East Street and is one of my favorite spots in this area. (Which matters because I live 200 meters away and know the area well!). There are also other outlets in Zhongxiao East Road and Linsen North Road (refer to their website)
Although the food tends to be on the pricey side at times, the food and drinks are excellent and my only gripe is that you have to wait at times for a table. The bar area is a bit compact, and it's better to get a table. After 10pm or so the focus moves away from dining towards drinking.
Overall, this Japanese bar and restaurant is recommended. The grilled Wagyu beef is exquisite to say the least. In fact, I'm so hungry after writing this, I think I might just saunter over right now!