Absolute Boyfriend

What do you get when you swap the traditional roles of a Magical Girlfriend series? A Magical Boyfriend series, of course! Absolute Boyfriend, or Zettai Kareshi, is a piece-of-fluff series by Yuu Watase (of Fushigi Yuugi fame) in which the lead girl -- Riiko Izawa -- gets her very own handsome dream guy... whom she orders over the Internet!

Riiko is a fairly average girl, a sort of female Unlucky Everydude (Everydudette?). She has had all of her professions of love rejected, and is completely oblivious to the fact that she is loved by the boy next door, who always teases her. One day, after lamenting yet another rejection, she finds a cellphone which she returns to its owner, who is a salesman and offers to sell her all sorts of things. When he asks her what she really wants, she tells him all she wants is a boyfriend.

So the salesman gives Riiko a Web address for site from which she can order a free trial of a "figure" which she assumes to be some sort of sex doll. She goes ahead and orders one, but when it shows up, it is freakishly realistic and good looking... and naked. When she kisses it, it awakens and is clearly besotted with her. She's freaked out about this at first (it, or he, thinks she wants to have sex with him... but fully respects it when she says "no"), but soon realizes he is the perfect guy. She names him Night, because he's part of the Nightly Series of figures.

He's only a free trial though, and she was supposed to give him back after three days; however, time runs out, and she is told she owes Night's creators $1,000,000! Luckily for her, she is able to persuade the salesman she met in the first place to let her repay them by teaching Night "everything about girls" instead (he's a prototype) and by forking over what money she does have. Thus, Night joins Riiko's class as Night Tenjo, and Absolute Boyfriend begins!

Yes it isn't exactly deep, but as Yuu Watase said, it was never meant to be.

For a same basic story with a gender-swap, see Yuria 100 Shiki.

Though there is no anime for the series, it has been adapted into an 11-episode Japanese tv drama and 1 special movie.

Tropes used in Absolute Boyfriend include:

A-Cup Angst: Riiko complains much about her flat chest in the beginning, which is, she's convinced, why boys aren't interested. Of course, boys are interested?
Anatomically-Impossible Sex: Parodied. When Gaku Namikiri says Night can "fire off" thirty rounds in one night, an arrow points to the speech bubble and says "death to mortals."
Anguished Declaration of Love: Soshi, after learning the truth about Night, gives one to Riiko.
Bishounen: Night. Lampshaded when he cross dresses to get work at a bar and the manager gushes about how convincing he looks.
Bitch in Sheep's Clothing: Mika
Bittersweet Ending: Night dies, but not before he and Riiko finally consummate their love.
- Actually Night dies because they had sex. His system re-adjusted to that of the loyal lover and he ran out of steam a month or two after the Big Night. Sex kills, indeed!
Boy In A Box: Night.
Breaking the Fourth Wall: One chapter in the manga begins with Soushi cooking dinner, then completely sidelines him to focus on Night and Riiko's developing relationship. At the end of the chapter Soushi angrily looks up demands "Am I going to do anything in this chapter besides COOK?!"
Catgirl: Riiko has to dress as one for a job.
Death by Sex: After Riiko and Night have sex, Night starts to get tired fast and constantly sleeps. Gaku mentions once to Riiko that she was making him do more than he was programmed to do, so sex on top of his experience as a boyfriend before that moment probably made him wear out faster than usual.
Expy: Gaku Namikiri shares the spunky attitude, Kansai Regional Accent, and Loveable Rogue tendencies with his predecessor from Fushigi Yuugi, Tasuki.
- Also the stoic, devoted, ridiculously good-looking love triangle loser Soushi is more or less Hotohori as a grumpy high school student.
- No, Soushi is NOT Tamahome/Tooya with glasses on. What gave you that idea? *cough*
First Guy Wins: Soshi is the first guy introduced with feelings for Riiko. It ends up being a subversion when Riiko chooses Night, but then when Night 'dies', Soshi comes back into the picture and will most likely end up with Riiko after all.
Gender Flip: Get used to it.
Gratuitous Spanish: Gaku, and also Night when his speech functions malfunction.
Hadaka Apron: Night once.
The Idiot From Osaka: Osaka-ben speaking Gaku Namikiri, who achieves a hat trick of Osaka associations: business (he's a salesman), comic relief (many, many times) and octopus (he's heir to his family's takoyaki stand). However, it's worth noting that Yuu Watase herself is from Osaka, so it also works as an Affectionate Parody of the stereotypes.
Improbable Age: It appears that the younger the Kronos Heaven employee is, the higher up in the hierarchy he is, cultimating in the company head being an infant.
Innocent Fanservice Girl: Or rather guy, read the description for Naked People Are Funny...
I Want My Beloved to Be Happy: In the 2009 special movie, the reactivated Night and the Nanase Jun robot both pull this. The Nanase robot lets his own main chip burn out over his creator's (who built him to replace her dead boyfriend) protests, because he realizes that an unchanging robot could never truly make her happy. When Night sees this, he realizes that the other robot is right and asks Namikiri to scrap him.
Just a Machine: At the end of the movie, Night invokes this to help Riiko let him go. When she asks him if he's only saying "I love you" because it's his programming, he says yes.
Kansai Regional Accent: Spunky salesman Gaku Namikiri.
Magical Girlfriend: Inverted, with Night as the Magical Boyfriend.
Mood Whiplash: For what started out as a romantic comedy, it sure has a Downer Ending.
Naked on Arrival: Night is delivered au naturel. Also a Naked First Impression.
Naked People Are Funny: Night, being a robot, is oblivious to societal taboos about nudity. Hilarity Ensues.
Overprotective Dad: Riiko's father
Parental Abandonment
Replacement Goldfish: In the special movie, the scientist responsible for finding a way to repair Night's main chip built a robot in the likeness of her dead boyfriend Nanase. Near the end, the robot tells her that he could never replace Nanase because, as a robot, he cannot raise a family, grow old, or change alongside her. He allows his own main chip to burn out because he knows he could never give her true happiness.
Sacred First Kiss: Riiko laments that this will be her first kiss, and that the man in question isn't even human.
Ship Tease: A significant basis for the plot; at various points, both Riiko/Night and Riiko/Soushi seem equally plausible. Watase herself had trouble deciding which one Riiko would end up with.
Shipper on Deck: Riiko's father wants her to be with Soshi.
Single-Stroke Battle: Parodied with Night facing off against Kronos Heaven's strongest fighters... and defeating them all without breaking a sweat.
The Snark Knight: Miyabe
Title Drop: Part of the Bittersweet Ending mentioned above.
Transgender: Gaku pretends to be, in order to get into a host club Night is working at along with Riiko.
True Love's Kiss: Surprisingly, and painfully, averted with Night's death. Riiko attempts to reactivate him with kisses several times before realizing that he's not going to wake up.
Unlucky Childhood Friend: The boy next door, Soshi.
- Victorious Childhood Friend: But only after his rival's death.
Unlucky Everydude: Gender-flipped with Riiko.
What Measure Is a Non-Human?: Riiko eventually grows to see Night as a human, or at least equilavent. Then Kronos Heaven Company does not.