So, you know how there's been a fad for "let's do something with the historical figure of Oda Nobunaga" anime lately? Most of them are silly or boring or both. This one... you kind of had to be there.
So, our main focal characters are a shy schoolgirl who's the reincarnation of Oda Nobunaga and a cool-type silver-haired bishounen who's the reincarnation of Jack the Ripper (only actually it's weirder than that). Together they fight alien monsters!
Along with the reincarnations of Mahatma Gandhi, lecherous schoolboy, and Issac Newton, busty blonde bombshell. You... kind of had to be there.
Our Heroine, Shiho, is a strategic genius when it's really crunch-time, and when she can take time out from madly fangirling the tanks and jets she suddenly finds herself surrounded by. Did I mention she's a total weapons geek without any influence from her "E gene progenitor" at all? She is. It's unspeakably cute when she starts getting shoujo sparkles over military hardware. And she invariably saves the day with her enormous gun. She's every shounen fighting trope ever, mashed up with every shoujo wallflower trope ever. I love it.
The best part, though, is how our focal characters are, in fact, a classic romantic trope! Kind of. They fight like cats and dogs, and only stop bickering to wreak bloody mayhem... at which point they really get along. They bond romantically over their mutual occupation as bloodthirsty psychopaths. They get these identically insane smiles. It's adorable.
...possibly you had to be there for that one, too.
The ending is a little abrupt if you're expecting several seasons of action, but if you watch it as, essentially, a one season romance of bloodthirsty psychopaths saving the world, it totally works. It also helps if you envision the writers running around behind the scenes jamming lampshades on every single trope they can cram in, cackling with glee all the while.
In short, I definitely recommend it!