Hotel LaPia
Regular Love Hotel with a few BDSM rooms: St Andrew’s cross, bed-installed restraints… ht: @Sondyr
Hotel S&M Rochelle ◆ ホテルロッシェル
S&M-oriented hotel, located quite far south from the the centre. Has a few rooms equipped with S&M gear (best to check online for availability before traipsing there).
Hotel Maxim ◆ ホテルマキシム
Love Hotel catering exclusively to BDSM. Choice of well-equipped rooms. Hotel is located well outside the city centre, and probably not worth the trip unless already in the general area.
Hotel Alpha Inn ◆ アルファイン
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