Tharbin

Tharbin is the non-binary ship between Tharja and Robin from the Fire Emblem fandom.

Fire Emblem Awakening
Robin and Tharja first meet when Chrom and his forces assault the courtyard of Plegia Castle to save his elder sister Emmeryn from execution. Tharja is among the castle defenders, but is apathetic about the ongoing war between her nation and Ylisse. Upon first laying eyes on Robin, something stirred in Tharja that made her realize they were the one she's fated to be with. Although Chrom is the one to recruit her, Tharja defects from Plegia and assists in the ultimately futile rescue attempt. She would go on to help Robin in ending the conflict with Plegia, as well as the later ones with the nation of Valm and the Fell Dragon Grima. During these conflicts, Tharja kept a close watch on Robin while concoting ways to make them hers.

C-A Support Conversations
While wandering around, Robin notices that Tharja has been following them for the last week. Although shocked that they knew, Tharja isn't completely surprised that it was them that saw her. She goes on to explain that she became infatuated the moment she first saw them and that she's been monitoring their every move, which she proves by revealing the number of books they read yesterday as well as that they had an apple for a snack and that they turned 12 times while sleeping - which Tharja notes is below average for them. Robin is utterly disturbed that Tharja's been following them from day 1 and suddenly finds themselves sick, which makes Tharja offer to take care of them. Robin rejects that offer since they note that - from a "normal" person - it would be less unnerving. Tharja takes note of Robin wanting a "normal" girl before running off, leaving Robin to fear what she has in store.

Sometime later, Robin runs into Tharja acting in an awkwardly cheerful way. Understandably, Robin is worried about this sudden shift in Tharja's personality, but she waves it off before feeding them a slice of liver-and-eel pie. To their surprise, Robin likes the pie, which prompts Tharja to comment that she'd been working on the recipe everyday after her "normal classes". From that comment, Robin suddenly realizes Tharja's attitude shift came from what they said the other day before profusely apologizing, saying she should never have listened to them and that they prefer the old Tharja back. At that, Tharja expresses worry that she can't stop given how diligent she'd been in her training.

Tharja does eventually drop her "normal" persona. When Robin takes note of this, however, they suddenly find themselves falling ill before passing out. Waking up, they find Tharja taking care of them, with her explaining they had a fever. Robin chalks it up to working too hard recently, which surprises Tharja as she figured they would blame her and one of her curses for it. Robin's horrified by that insinuation, stating only a monster would curse a friend like that - even though Tharja chuckles awkwardly at that. Regardless, Tharja notes that Robin once said they didn't want her to take care of them, which they say was a mistake on their part before falling asleep. While watching Robin sleep, Tharja can't help but note how cute - and vulnerable - they are right now.

S Support and Ending (M!Robin only)
While walking, Robin tells Tharja that it's time to stop following him from behind so closely. When Tharja asks why, he explains he wants to see her face before deciding to just turn to her. The two realize it's the first time they've actually been face-to-face, with Robin noting that he likes it and would like to keep doing it forever, prompting him to give her a ring. Robin reveals to Tharja that he loves her, but she's so shocked about the proposal that she has to take a moment to collect herself. For his part, Robin admits that the idea of being together is still settling in him. As Tharja muses about how Robin finally made her love him, she warns not to back out of he'll be dead in his sleep. Following the defeat of Grima, Robin many exploits were written, and while a lot of the details varied, future generations noted one consistent detail was that he loved Tharja above all else.

Fire Emblem Heroes
Tharja and Robin are two of the heroes that the player can summon separately via the Breidablik using orbs to help Alfonse and his sister Sharena defending their kingdom Askr from the Emblian Empire. As in their original game, Tharja and Robin can develop a bond via support. They can raise their level of support in the following ranks: C, B, A and S if they stand together in the gameplay. Each of them have variants beyond their base forms: Tharja has three solo variants and assists as part of a duo hero while Robin, between both genders, has six solo variants and also assists as part of a duo hero.

Tharja and the male Robin are both enemies in the first part of Chapter 8 of Book I. After Robin addresses the Order of Heroes, he's surprised to see that Tharja is there with him. When he questions if she's following him again, Robin drops the subject and instead has her help him against the Order, although the two are defeated.

Tharja and the male Robin both received Holiday variants in the Winter's Envoy focus from December 2017. In the associated paralogue, Tharja - attempting her "normal" persona again - is happy to be spending time at the Winter Festival with Robin, but he's trying to point out to her that their in a tournament. Tharja doesn't listen as she muses how her "old self" would be cursing all the couples at the festival, much to Robin's chagrin. Upon the two being defeated, Tharja breaks character and begins swearing that she'll curse the enemies while Robin gets her to regroup for the final round.

Fanon
Tharbin is a popular ship in the Fire Emblem fandom. Tharja's devotion to Robin, specifically, already serves to give the ship a good foundation. However, it's helped even more by the fact that Tharja's attitude about Robin is the same regardless if their male or female. This has led to the implication that Tharja is either bi or so madly obsessed with Robin that she'll love them no matter what they look like. As a result, there are slightly more fanworks featuring Tharja paired with female Robin, although the male variant still has it's fans. Many consider Rhajrrin as the successor/evolution of this ship due to Corrin and Rhajat having the same dynamics as Robin and Tharja (and Rhajat even being implied to be a reincarnation of Tharja) while also being able to same-sex S Support.

With all of that said, this ship isn't seen favorably by some. Detractors take issue with Tharja's obvious stalker attitude around Robin, seeing it as rather unnerving and creepy. It's also not helped by this ship having rivals on Robin's side such as Chrobin and Robcina.

On AO3, this ship is fairly well written about, with tagged works in the 210's range. This is Tharja's most written ship. On Robin's side, it's their third-most written ship behind Chrobin and Robcina.

Fandom
FAN FICTION

Trivia

 * Tharja has unique quotes when standing on an Event tile while paired with Robin or when the two are in the Barracks. She's the only character with this distinction.
 * In the confession CG for Robin's and Tharja's S Support, the bubble background is green instead of the pink used in other Confession CGs. This is likely a play on the term "green with envy", which fits Tharja's possessiveness of Robin.