Discretion

It's the middle of the night. I'm quietly making my way to the bathroom in the dark not to wake up Oskar and Wolfram.

I sat on the toilet and suddenly it makes the sound of flushing. That's the feature to mask the sound of peeing. 

Might be a great feature during the day but at night it's making loud and clear that you are visiting the toilet.

Luckily no one woke up.