[[caption-width-right:170: Mako is more than just a girl.]]
''Boku no Futatsu no Tsubasa'' is a manga by Yui Toshiki.

Hiromi is very excited that her cousin Makoto is coming to stay with her and her mother. Hiromi remembers playing with Mako when they were little and is hoping “he” has grown into a handsome young man. However, when Makoto shows up as a very buxom young woman [[HilarityEnsues it starts of a chain of misunderstandings, secrets and cover-ups]].

This is an {{Ecchi}} manga and features adult situations, explicit sex scenes, and nudity. Some of this is played up as fanservice, but there is a lot of sex tied into the plot as well.
!!The manga includes examples of:
* ADateWithRosiePalms: Mako-chan, which often leads to...
** CaughtWithYourPantsDown: As Hiromi frequently walks in on her.
*** CovertPervert: And then assertively proceeds her molestations of Mako, with contrived reasons like "if you let it build up and have a wet dream, you could...get YOURSELF pregnant! Seems I'll just gave to overcome myself and help you, for your own good," and flustered explanations that she couldn't possibly be doing it out of interests (all to appease her own confusion over her attraction, oblivious of how the constant rejection - in the most intimate of moments, no less - hurts Mako, and makes her already highly unusual view of sexuality progressively more skewed)
* ActionGirl: Mako can kick much butt when the need arises.
* AllMenArePerverts: Averted with Hisamatsu, but played straight with his friend Keigo...and Mako.
* AmazonChaser: Keigo suddenly becomes interested in Mako after she beats up a group of muggers trying to steal her mobile telephone.
* AmbiguousInnocence / KidsAreCruel: various bungled attempts to figure out their sexualities inflict pain generously all around, mostly obliviously so, especially coming from the utterly naive Mako (whose unique situation and alien views hardly help), but nearly as much so from Hiromi, whose meticulously constructed wall of denial makes her about as clueless
* BarbieDollAnatomy: Runs on the standard Rule of {{Ecchi}} -- nipples are fair game, genitals aren't drawn.
* BerserkButton: Don't call Mako-chan a monster.
* BiTheWay: Both Makoto and the resident Casanova. [[spoiler: For Makoto it's inherent in her biology though she eventually settles on women.]] The latter is [[AnythingThatMoves not all that choosy to begin with.]]
* BizarreAlienBiology: [[spoiler:Mako-chan and her father.]]
* BoldlyComing: Inverted. Here, it is the aliens who initiate "first contact", and not because MarsNeedsWomen.
** Perhaps double subverted, as it is [[spoiler: Kanako]] who actually initiates the affair when she gets bored and lonely as a guest on the alien ship.
* BookEnds: It starts and ends with Hiromi opening the door, expecting somebody else, and [[spoiler:being surprised when Mako arrives. The panel layouts and character movements are the exact same as well.]]
* TheBusCameBack: With a quintessentially alien profession of love. In an oddly fitting, and to her, supremely romantic way.
* BuxomIsBetter: Most of the guys, [[SchoolgirlLesbians and a few of the girls]] are impressed with Mako-chan's ample chest, which is an F-cup. (Japanese sizing, but still big)
* ComicallyMissingThePoint: Lovable airhead that she is, Mako's response to her "dad" giving a detailed explanation of how the member of their species are naturally hermaphroditic, about their home planet and about how they came to Earth and Mako was born, is repeating her initial exclamation upon meeting: "My dad is a ''woman''?". Mako's dad all but facepalms.
* EverybodyWantsTheHermaphrodite: [[spoiler:Mako herself]] seems to prefer girls: she has the thought that the only people who really accepted her as she was were girls. (The two guys she dates don't exactly leave her a great impression of men.)
* FamilyRelationshipSwitcheroo: After the reveal that "Aunt" Kanako is actually Makoto's mother it dawns on Hiromi that she and Makoto are actually stepsisters instead of cousins.
* GagPenis: From her bouts of morning wood and states of arousal, it can be drawn that Makoto is ....well endowed for her age.[[spoiler:Which serves to hurt her first relationship with a man when it's implied that she's actually bigger than him]].
* GainaxEnding: More of a highly rushed ending, but it does resolve the plot in an almost lightning speed manner that is a little confusing to follow.
** The majority of the series is spent being a kind of SliceOfLife RomanticComedy revolving around how to keep the fact that Mako is a [[spoiler:hermaphrodite]] a secret with a mysterious force in the background. The last few chapters kick in with it being revealed that [[spoiler:Mako is actually an alien, people want her to hold for ransom so they can get alien technology from her father, she then goes back to her father's homeworld, seemingly disillusioned with Earth and gone for good... and suddenly appears, months later, on Hiromi's doorstep in the last few pages, sheepishly but nonchalantly stating she reconsidered just because she realizes that she absolutely ''must'' screw Hiromi properly, no matter what, and nothing else matters.]]
* GlowingEyesOfDoom: When [[spoiler: Makoto's alien powers kick in.]]
* HappilyAdopted: Hiromi, though we don't find out until after she and Makoto engage in some borderline (and not-so-borderline) incestuous behavior.
* {{Hermaphrodite}}: [[spoiler:Mako]] has both male and female genitalia.
* HugeSchoolgirl: Mako is between 175cm and 180cm. Her height is commented on a few times, mostly by people asking if she's grown.
* [[spoiler:[[HumanMomNonHumanDad Human Mom, Non-human Mom/Dad]]: Mako and her parents.]]
* IfItsYouItsOkay: [[spoiler: aggressively lesbian Kanna's reaction to being deflowered by Mako, commencing an unexpectedly heterosexual-style affair, where Mako consistently boinks her lesbian lover using the ''boy parts'']] and also straight with [[spoiler:Keigo]]. Averted with [[spoiler:Hisamatsu]] who says they're okay with it but when it came down to it... it didn't go as planned.
** On a meta level, Mako's [[spoiler:hermaphroditism]]. Everyone who learns of it accepts it; none of them ever try to out her to the world at large. The ones who struggle most with the concept are, strangely (or perhaps tellingly?) Mako and Hiromi.
*** Complete understanding and eager full mutual acceptance of each other as the curtain falls.
* InterspeciesRomance: [[spoiler:Makoto's parents]]. And to some extent, every romance involving their daughter is that.
* LethalChef: Eating all of Makoto's bentou is a [[DontTryThisAtHome very bad idea]].
* LoveTriangle - subverted: both Hiromi and Mako separately engage in meaningless sex with Hiromi's womanizing ex to push each other away at the worst possible moment and unwittingly hurt each other, though Mako has no clue that it's also serious for poor Kanna.
* [[spoiler: LaserGuidedAmnesia deployed on Mako's decision to leave for her father's world]] makes it all better for everyone except Hiromi, who alone remembers everything. And is deeply traumatized by the experience, having finally started to figure out what was going on and how she felt about it all. [[spoiler: until Mako, who surprisingly understood it all too - albeit in her own way - swaggers onto the final page to blatantly announce that she's back because she remembered she'd never got the chance to have sex with Hiromi. Hiromi's reaction implies she knows she's teasing.]]
* [[spoiler:LukeIAmYourFather: Hiromi's adoptive mother is actually Mako's mother.]]
* MakingLoveInAllTheWrongPlaces: Both Makoto and Hiromi use the nurse's office (not with each other), and Mako also makes use of various other locations around the school with Kanna.
* NotBloodSiblings: After some accidental (and some not-so-accidental) incestuous behavior, Hiromi reminds Makoto that she is adopted -- meaning they are not blood cousins. [[spoiler: It also means that they are not blood sisters either when Hiromi's mom Kanako is revealed to be Makoto's mother, but stepsisters by way of adoption.]]
* OlderThanTheyLook: Ayame looks like she's about twelve.
* PlayingDoctor: Mako-chan and Hiromi as kids, leading to some amusing misconceptions.
* PornWithPlot: The balance shifts
* SchoolgirlLesbians: Kanna, Tamami and [[spoiler:Hiromi, sort of.]]
* TheTease: Makoto teases the heck out of Hiromi early on as payback for Hiromi first trying to peep on her to discern her true gender and then acting uncomfortable when her suspicions are confirmed.
* [[BrotherSisterIncest Sister Sister Incest]]: [[spoiler: Mako and Hiromi at the very end]] though they are NotBloodSiblings, they're stepsisters by adoption. The reveal is a bit... [[AssPull sudden]] though.
* TeacherStudentRomance: Mako catches Keigo cheating on Hiromi with one of the school's teachers...who also happens to be Kanna's older sister.
* {{Transsexual}}: [[spoiler:Tomoki]] describes herself as "a girl trapped in a boy's body".
* YuriGenre: A good part, if not most of the romances are between girls. Although [[spoiler:Mako]] is [[spoiler:a hermaphrodite]], her female side is clearly predominant [[spoiler:(except during sex)...there's a reason "she" uses 'boku']].