Yep! The washing machine event has a 15% chance to happen. Every time you go to sleep, the game rolls a random number for the next day. If you get lucky you can get the washing machine event on first try. Otherwise, you'll get the default laundry event.
As for the Gallery, I'm currently not planning to add every sandbox/repeatable scene there. I want the Gallery to focus more on the major story scenes. I might change my mind in the future, but for now those scenes are only available by playing the game.
About Hanabi:
- If you steal from the Hyuuga estate, you have a chance to find her diary. If you keep it instead of selling it, you can read it from your inventory, which starts her storyline.
- If you steal both her diary and panties, the Black Merchant will offer you a deal. Accepting it starts her quest immediately. If you refuse, she'll instead visit your house after Day 5.
- If you never steal the diary at all, she should also come to your house after Day 5.
(That last path had a bug in older versions, but it should be fixed now.)