Most famous SM-oriented Love Hotel in Tokyo. Large number of rooms with misc SM/rope equipment. Friendly staff.
Some equipment and amenities are past their primes and rates (esp overnight) aren’t cheap.
There is a completely unofficial (and not officially-sanctioned) tradition of open-door system, where people looking to play with/in front of other people, leave the door to their room open (needless to say: if a door is closed, do not under any circumstances attempt to go in).