This Leiji Matsumoto manga series first ran in 1970-1. It was compiled into two tankobon volumes in 1978.
1970. Mamoru Oguchi is fired for a single slip of the pen, one mistaken word that has cost his company a lot of money and pride. He wanders off into the forest with a vague intention of killing himself with his rifle. But then he runs into a beautiful woman lying on the ground. He gives her water and she leads him to her…spaceship. Her name is Eve, and she’s an observer from far, far away (specifically from Salus, the 20th planet in the Seselaselarium Natria Herania Lasu-Ulpania Solar System of the Etus Nebula) who’s had a mishap and crash landed in the forest.
Eve tells the man if he helps her fix the ship she will upload to his brain all of the data she’s collected regarding Earth, which happens to be virtually everything there is to know about the planet, its people, history, etc. After considering things, Mamoru unloads several shots of his rifle on the ship and destroys it. He tells Eve that he can’t risk helping her escape and then having her obviously superior civilization attack and take over the Earth at some later point. Eve is amused, and she informs Mamoru that since he’s destroyed her ship now she’ll have to stay with him forever…
Thus begins Mystery Eve, with a premise that can be recognized in a great many Japanese manga, and indeed in fiction around the world. The classic formula always goes like this: living with an unusual creature/alien grants the protagonist access to all sorts of cool abilities and gadgets BUT the alien’s idiosyncratic actions and the hosts of enemies the aliens attract are enough to counterbalance and even offset all of the positive effects.
For example, Eve is so thankful that Mamoru is “keeping” her that she decides to upload all of Earth’s data into Mamoru’s brain anyway, so he can speak all the world’s languages at will etc. But when he goes to interview for a new job, he comes off as so clever that the company boss accuses him of being an industrial spy and refuses to hire him. Mamoru manages to find work at another company, but now he gets fired because in analyzing the company data he’s forecasted how the firm will do for years to come, and the boss is worried his rivals will get a hold of this analysis and undermine his company. On top of these travails, Mamoru has to deal with Eve’s boyfriend coming to rescue her and attacking aliens from a rival nation (the Heds) in Eve’s home planet.
Aside from the working out of this formula, the series is also driven by its relationship with Matsumoto’s prior work Sexaroid (1968-9). Mystery Eve starts off as an upside-down Sexaroid. The male protagonist in Sexaroid, Shima, gets tired of the android Yuki’s constant sexual demands while running about with a variety of other women. Here, the alien Eve is a shapeshifter and she is fond of assuming the form of women Mamoru might like so he doesn’t have to go elsewhere. In fact, Mamoru is constantly worrying she will return to her home planet and leave him.
Though showing promise, the series begins to drag after a while. Chapter after chapter begins on a crazy note only to end with the same exact struggle between Eve/Mamoru and the enemy Heds, who are more or less human-looking except for two things: they’ve got tails and super-soft bodies that can be destroyed easily.
Also, Mamoru begins to sleep around and remind us more and more of Sexaroid’s Shima. Mamoru’s ladies start to die and three or four chapters end with him weeping over the dead woman with Eve by his side, just as Shima does with Yuki. In the last chapter of the first volume, Mamoru is contacted by an international agency that knows of the Hed threat and intends to eliminate it. The boss looks just like the boss in Sexaroid—it’s no exaggeration to say that by the end of Volume 1 the series Mystery Eve has turned into Sexaroid!
EXCEPT for the little fact that in the first chapter of the second volume (ch. 14) we find out that this whole agency is a sham run by the Heds and that the boss is a Hed himself! So after their defeat we’re back to the regular pattern.
Then in Chapter 20, Mamoru and Eve are kidnapped by the Heds (again!) and taken to their home planet in Etus (the trip evidently arriving sometime in the future). Of course, this is not only the Heds’ planet but also Eve’s. Sadly for her, her race (which populated the northern hemisphere) has been exterminated and so by the end of Chapter 22 the couple has found a way to return to Earth on a spacetime machine. This sets up the craziest scene in the whole series. The two arrive on Earth millions of years ago, before there was any life on the planet. Mamoru empties his bladder on a rock on the beach and we learn from the translator that out of the mixture of the seawater, the rock minerals and Mamoru’s urine was born the first spark of life on the planet. The reader is left speechless.
Something to be said for this story is that it has a proper ending. Back in the present time and over at the Etus Nebula, the Heds begin to invade and conquer Eve’s people (let me call them Evites now on). The Evites blame Eve’s failure as their eyes and ears on Earth for the disaster and so they whisk her back to Etus and sentence her to death. Mamoru immediately makes his way there. Things get really desperate for the Evites on their planet and they decide to invade and conquer Earth—this won’t be easy as their enemy the Heds have been slowly but surely planning the same thing all along.
Mamoru and Eve escape from the Evites, hop on a combat vessel, and destroy the remainder of Eve’s race (which was setting forth to conquer Earth), then return to Tokyo. We realize now that the extermination of the Evites in the future, begun by the Heds, was actually completed by Eve herself. She is now truly the last of her race. This “betrayal” is justified by the Evites selfish decision to destroy one people (Earthlings) to save themselves. In addition, Eve makes the point that her people have obviously outrun their natural lifespan as a nation, as their inability to defend themselves from the Heds has shown.
The story could have easily finished here (ch. 24) but Matsumoto for some reason added an extra finale chapter (25). The availability of time machines means that one can’t ever be sure that a race has been fully exterminated. Even if, say, the human race expired in 2012, humans with a time machine in the year 2000 could travel to a future Earth and repopulate it etc. This is what happens here: a group of Evites from a time before their destruction reaches Earth. Happily, they decide to assimilate and live as human beings. Weirdly, one of the Evites asks Eve for one last sexual encounter so they can feel what their glorious race was all about, and Eve agrees! And Mamoru doesn’t oppose it! And with that the true end of the series arrives.
This series might be charming if you’ve never read Sexaroid, but if you have then you’re likely to be bored. Not only that, but the gamut of women in Sexaroid seem to have slightly more in the personality department than the ladies here…
NOTE: There’s a funny sequence I’d like to point out. It’s at the beginning of chapter 8, when an impostor posing as Eve applies for a position in a corporation. I like what Leij’s done with the relative sizes of the objects and the angle of the cigarette. The boss has just asked her if she speaks English, and she replies: “A little”. “How about German?” “A little.” “And Chinese?” “A little.” “Well, I have no choice but to make you my personal secretary!”