David, this is a low end model. There are/were more expensive toilets. The buttons are for male/female as in where to spray the water hot/cold water and the intensity of the spray. Americans don't get bidets but they are quite popular in most of the world and honestly I feel they are a more sanitary way of cleaner your nether regions after using the bathroom. The sink toilet combo is great you wash your hands after you flush with the water that is filling the toilet back up. The Japanese are ingenious about recycling everything. It is one of the things I love about Japan. That and I miss vending machines full of hot/cold coffee/tea on every street corner. Oh and Japanese baths or furo are awesome. It's electronic as well. You push a button to fill the tub to a preset level with a preset temperature. Once it reaches both it beeps to let you know its ready and it recirculates the water through a heating system under the tub and your water always stays hot. Japanese tubs are for soaking not bathing. You always bathe before you get in the tub.
One of the coolest things I saw was my neighbors had a Panahome built by Panasonic. It had electric everything; solar panels on the roof, electric storm shutters, the windows would turn dark at the press of a button and on and on. It was a sweet house. Stuff you would never ever see in the USA. Japan is decades ahead of us when it comes to most technology/transportation.