Iron Widow (Iron Widow, #1)
by Xiran Jay Zhao
Whew, that was.... A Lot!!! Maximally chaotic bisexuals piloting giant robots to fight aliens; somewhat gory.
A little explainy about Feelings and Feminism, but not annoyingly so, and I appreciated the way the explanations were used to keep the plot thundering ahead at breakneck pace. The ending was absolutely bananas; I don't even know that it needs the second book, honestly, just leave us with that.