On many Japanese toilets, the hand wash sink is attached so that you can wash your hands and reuse the water for the next flush. Japan saves millions of liters of water every year doing this.
I can see some commenters are confused. The water only runs whilst the cistern is being filled after a flush. It will be cold water and only so you can wash your hands after using the toilet, not for you to brush your teeth or wash your face. If you use a gel liquid hand soap it won't get all scummy inside the cistern after you wash your hands.
This is only for handwashing after using the toilet. Nothing more.
AudienceSimilar on June 8th, 2021 at 18:56 UTC »
So Butters was right
Supercereal69 on June 8th, 2021 at 20:14 UTC »
That's why I pee in the shower
votisit on June 8th, 2021 at 20:21 UTC »
I can see some commenters are confused. The water only runs whilst the cistern is being filled after a flush. It will be cold water and only so you can wash your hands after using the toilet, not for you to brush your teeth or wash your face. If you use a gel liquid hand soap it won't get all scummy inside the cistern after you wash your hands.
This is only for handwashing after using the toilet. Nothing more.