I think your expectations as to the amount of analysis I have given to a theory I have called "A"lien "S"pace "S"pider might be a bit high
I will however explain my thought process:
1. Be Selebus
2. Want to make people cry (which is synonymous with number 1)
3. Have a character who speaks as if they are not human and has a spider tattoo
4. Have a nebulously defined space war
5. Remember Starship Troopers
6. Consider what would be a truly horrific moment to add to a sex scene that would achieve 2
7. Pedipalps (think Edgar from MIB)
8. Feel smug while vomiting a little bit in my own mouth
If I thought I was seriously expected to engage with the concept of a space war (outside of it being a convenient maguffin to explain the lack of men) it makes sense to me for it to be against aliens as otherwise it would be a colonial war for/on a planet and it would be like "The Martian War" or something similar.
Unless Gundams exist I guess.
LIL confirmed to be in the Gundam Universe?