There are quite a lot of stairs to climb at this venue, especially since the bar and the live house are on separate floors. There are 2 flights of stairs to climb to get to the room where the bands play. Then there are another 2 sets of stairs to go down to the bar. Once you are in the room where the bar is, there are even more steps to get to the actual bar. In the room where the bands play, there are some places to sit down, but all of the bands play on the floor, so it might be difficult to see if you aren't up front or near the front. There is a elevator that takes you to the room where the bands play that is used for bands to load their gear in and out. I am sure that if you talk to the promoters they would be happy to let you use it so you don't have to walk down the stars. However, the elevator does not go down to the floor that the bar is on.
The bathroom is adjacent to the room where the bands play and there are no steps to enter it. It is a western-style toilet so it is possible to sit down. The bathroom is not large, but not tiny either.
〒542-0086 Osaka Prefecture, Osaka, Chuo-ku, Nishi Shinsaibashi２-９−３６, Japan