Speaking of hard science fiction, we have this anime series about survival. Set in the far future, a pair of twins are accidently convicted to a secret prison planet. The planet is known by those there as "Jyu-oh-Sei" or "Planet of the Beast King." Which means you have be like a beast if you want to survive.
It's a nasty planet to be sure. The flora is homocidal, it's like the planet of little shop of horrors. Worse, there is one hundred and eighty days of light, and one hundred and eighty days of night. That means at the worst of the cycle it gets up to 90 degrees c and at the worst minus 40 c. Survival, is a constant question.
The people don't help much either. Being convicts they aren't warm or cuddly. They've formed something of a society but not much. The most interesting thing is that the women are given the top spot as they are rare there.
Certainly interesting and if you like science fiction worth a watch.