It would be interesting to know if there are such rooms available...
btw (im not sure, that why i asked) what exactly are the things u are looking for that are similar to the Japanese love hotels? round beds? mirrors on the ceiling or 'toys' on demand service?
Siloso Beach Resort has some really nice Garden Roof Suites... has a glass tub on an outdoor private terrace which only you have access to via a flight of steps in ur room...if you don't mind your neighbours hearing you when u guys are having ur fun in the tub
We stayed there twice and it was really great!
Scarlet Hotel is quite cool, but it is more likea fashionable hotel...love the room finishes although the bathroom is WAY too small