Tsubasa & Hikaru tells the story of a 10-year-old girl, Tsubasa, who suddenly has to leave her lifelong home to move to a rural area of Hokaido along with her father, who wants to start a new life project, working in a local bakery while learning the trade as he goes. To all this, obviously our little protagonist is not very enthusiastic, because a move involves moving away from everything she knows, as well as from the bonds she has formed throughout her short life. However, with a forced smile, she tells her father that everything is fine and they leave for their new home.

Once settled in Hokkaido, we can see that our protagonist, of an introverted nature, has a hard time making friends or even striking up a conversation with a classmate, leading her to adopt a quiet attitude and distance herself from the group, which ironically begins to work against her, since some of the students misunderstand Tsubasa, believing that being from the big city, She is a conceited girl who belittles the other children in the village.

Starting off on the wrong foot, and regretting having said yes to his father when he asked him to move, Tsubasa returns home with his spirits on the ground and wanting to go to bed and end that horrible day. However, to his surprise, he sees something resembling a shooting star, which suddenly falls into the forest near his ranch. Given the commotion, the local dog (yes, there was a dog, sorry for not mentioning it before) runs to the point where the curious phenomenon occurred, causing our protagonist to chase him worriedly. When she arrives at the place, finds a most extravagant scene: a crashed ship, and next to it, a humanoid figure of male appearance and a strange being that seems out of control, are in full fight. With no time to react, Tsubasa sees the strange being rush towards her, grab her by the foot and throw her into the ship, where she hits a mysterious tube that, when broken, fused with her, giving rise to a humanoid figure of female appearance very similar to the one mentioned above.

Once turned into this "new being" Hikaru manages to finish off the monster mentioned above, with the help of the instructions of the man who had arrived with the ship, who was lying on the ground, after being hit by the monster.

Once the danger is over, the male humanoid being reveals his true appearance (almost indistinguishable from a human being), and it turns out that the strange appearance derived from the fusion of him with a kind of "living liquid metal" that they use as armor, which cannot take form, unless someone is using it, but once separated from the user, it is again a formless liquid and nothing more. However, to everyone's surprise (or maybe not so much?) when Tsubasa returns to her normal state, we discover that there is... 2 Tsubasa?, since for a reason that we do not know, this liquid metal has taken the form (and memories) of our protagonist, thus forming a new being, the aforementioned "Hikaru". And in this way, the first episode ends, which introduces us to the world and narrative of "Tsubasa&Hikaru".

Now you may be wondering why I made a summary of the first episode and the answer is simple: to fill in the necessary characters xD well, and because I think it's a good way for you to have a general idea of the tone of the anime, However, I don't want to tell you the whole story, but, give you a general overview of the topics it deals with and so you can decide if it's really what you're looking for, without fear of being filled with spoilers, since I do not consider it necessary.

At first you might think that Tsubasa&Hikaru is an action anime where we will see our two protagonists, fighting against these monsters that have spread across the earth because of the crashed ship, and they would be right, but only in part.

Because the real objective of the show is not to show us how Tsubasa becomes more powerful and becomes the great heroine of earth, but rather delves much deeper into topics such as personal relationships, how a person reacts in a new environment and how bonds, or lack thereof, affect our personality and the way we see and develop in the world.

To illustrate my point, I'm going to focus on explaining what I think are the most important themes around which this anime revolves and I'll limit myself to giving an example of how these themes are addressed, so as, again, I don't go into too many details that can ruin the plot.

The first and most important, which I have already briefly mentioned, are the bonds and how they transform us. the clearest example is how Tsubasa, a withdrawn, quiet and fearful girl, with the help of Hikaru, who is her opposite (ironically, despite being a copy of her appearance xD), finds the link that makes a bridge between her and the rest of her classmates, because now she has someone to lean on and gives her the confidence to open up a little more to others. Like this, we have other cases throughout history, where these bonds are worked on, and we can see how each group has its own dynamics and even how the same individual can behave differently depending on who they are interacting with.

Another important theme that deals with and is directly related to bonds is that of dependence and the search for one's own identity. As an example, during the development of the plot, we can see how Tsubasa becomes more and more dependent on Hikaru, to the point that she does not believe she can do anything on her own, since she needs to know that she has Hikaru behind her, who acts as emotional support and compensates for the "deficiencies" in Tsubasa's personality.

However, as Tusbasa gains confidence and meets a certain person whom she considers "special", we can also see the need to forge her own identity, moving away from being just Hikaru's "twin" and becoming more independent, dating that person alone, not communicating anything to her "sister" and thus forming her own memories, unique and private, of which Hikaru has no knowledge.
This may seem childish nonsense to us, but it sets a pattern in the evolution of Tsubasa.

Finally, I want to mention loss, as another central theme of this story. From the beginning, it is made clear to us that Tsubasa has had to deal with the loss before, due to her mother dying shortly after giving birth to her. Although it could well be said that she did not have to experience it first-hand. However, with the arrival of Hikaru, a farewell is also inevitable, since from the beginning they make it clear to us that she is an entity from another planet, that she is on earth for the duration of her mission and that sooner or later, she should leave.

Without wanting to go into more details, I think we can all feel identified with that feeling that comes from the loss of an intense bond, one of those in which we rightly or naively rely and without which we would feel an immense emptiness. Well, this is what "Tsubasa&Hikaru" raises, the importance of bonds, their transformative power and the volatile and ephemeral nature that they can have. Is it worth forming a bond that you know won't last forever? How to deal with the emptiness that remains after the loss of a bond? Are memories enough to heal that emptiness and move on? Those are some of the questions I've asked myself after finishing this story and if you're like me and like to ask yourself tough questions, you should definitely give it a try.

I recommend this show for anyone who is dealing with the loss of a loved one or who finds themselves aimless, trying to find their place, and maybe it will be a little difficult. Or if you're just someone who likes to ask yourself tough questions, I think those kinds of people will find in this anime, a little hidden gem.

PS: I apologize in advance for any mistakes or difficult to understand phrases, as I use a translator since English is not my native language. Also, I know that my review may be poorly written, but I thought that this anime really deserved some love and if it helps someone to know this little forgotten gem, I will consider myself satisfied.