Nihonbashi Maruei is a Japanese restaurant in Nihonbashi, Osaka, serving unagi don, katsudon, and udon. The unagi don comes with soup, and curry katsudon and udon can also be ordered. Entry is immediate right after the 11 a.m. opening, while around 11:30 the wait is about 10 minutes. The seasoning is on the salty side, so diners look for water by the end of the meal.