Use your rational human agency that dismisses AV and upset the natural balance of the planet. Eg find a nice smooth pebble on that island and bring it back to other side of the globe . A tangible act that will actually affect the wobble of the Earth, just because you can
I absolutely LOVE the idea!!
As far as your bf's family is concerned, don't allow them to rent space in your head and ruin your vacation. The only person you can control and the only person you are responsible for (I assume you don't have kids) is yourself. If they want to go through their vacation feeling bloated and hungover half of the time, it's their choice. As a non drinker with a clear head, you can really make the most of your time in Japan.
Is it too much to hope that you will post a couple of fabulous pictures of the landscape here? >hint< >hint<