Definitely check out The Left Hand of Darkness from Ursula K. Le Guin! The story takes place on a planet where people have no gender, but develop male/female features once a month, and the book explores how such a society might look like.

Correct!

Drawing lines to open doors

Correct!

More boosters

Dwarf Fortress?

Have fun! Five Parsecs lends itself nicely to cooperative play. My girlfriend and I usually play by either deciding on a course of action together, or by each of us controlling half of the team.

To get started, there’s also a great ongoing YouTube series by Trevor Devall from Me, Myself and Die!.

Dawn of the Zeds is great! I also really enjoy Nemo’s War from the same publisher.

• I love all the Buttonshy wallet games: Sprawlopolis, Rove, and Food Chain Island in particular are great.
• Maybe a bit on the heavier side, but I currently really enjoy Imperium: Classics/Imperium: Legends. They have a great solo mode and really scratch that deck building itch.

There’s also Five Parsecs from Home, which is a solo wargame / RPG. You only need a handful of minis, and it’s miniature-agnostic so that you can use any mini you want.