Having every second week a Friday off (or random other weekday, if I announce it ahead of time) gives me an amazing amount of breathing room and flexibility com

Having every second week a Friday off (or random other weekday, if I announce it ahead of time) gives me an amazing amount of breathing room and flexibility compared to my girlfriend who has to be on the clock 10:00-16:30 ("key hours") every day of the week without fail (well, holidays, but those are planned months ahead and not flexible at all). It docks 10% of my pay but it's so worth it.