Dimileth

Dimileth is the ship between Dimitri and Byleth from the Fire emblem fandom.

Pre-Academy
Dimitri and Byleth first meet when Byleth and their father, Jeralt rescue him along with, Edelgard and Claude from bandits. Byleth's display of bravery and skills as a mercenary greatly impresses the three lords. Much like the other two lords, Dimitri praises Byleth for their battle prowess and proposes that they return to the kingdom with him to lend their services. According to Byleth's first impression of Dimitri, he seems to be a sincere man but they sense a darkness within.

Byleth and Jeralt are summoned to Garegg Mach Monastery. Upon arriving at the monastery, the three lords walk alongside Byleth to which Dimitri offers to show them around. Byleth is then given the choice of leading one of the academy's three houses in which Dimitri is the house leader of the Blue Lions. Before making a final decision, Byleth is tasked to talk to the house leaders about their class. Dimitri apologizes to Byleth for not formally introducing himself the other day and once again, thanks them for rescuing them.

Blue Lions Route
If Byleth chose to teach the Blue Lions, Dimitri and Byleth slowly grow closer over the moons. Dimitri thinks highly of Byleth's skills and will often shower them sincerely with praise. Despite this admiration though, Later on in White clouds, Dimitri admits to Byleth that their lack of emotion bothered him and that they didn't seem to have strong feelings about killing their enemies. However, in the half year that they spent together, as he gets to know them better, he sees that Byleth isn't at all like that and that he can trust them with all his heart.

Dimitri doesn't come off unhinged for some time until their hostile encounters with the Flame Emperor and Those Who Slither in the Dark which slowly drive Dimitri to become more ruthless. After the remire village incident, Dimitri tells Byleth about the Tragedy of Duscur which took the lives of his family and close friends. Being the only survivor of the tragedy, Dimitri reveals to Byleth that the reason he came to the academy is for revenge.

Later on during the Ethereal moon, a ball is held. Byleth steps out of the celebration only to come across Dimitri who was also worn out by the festivities. Dimitri confides to Byleth about his stepsister, Edelgard. He recalls the fond memories he shared with Edelgard as a child and how he gave her a dagger as a parting gift. Byleth insists that he should reconnect with his stepsister but he says its far too late for that. If Byleth chose Dimitri for the goddess tower event, he will invite Byleth togo with him to the tower. Otherwise, he will go back to the ball.

After Jeralt's death, Byleth is stricken with grief and refuses to go out of their room for some time. When they do come out, they go to Jeralt's quarters to read his journal. Instead of Alois, such as in Black Eagles and Golden deer, Dimitri himself will come to see Byleth to check up on them. Dimitri, seeing the emotional state of his professor, consoles them and tells them that its okay to cry because eventually, their tears will dry and that you have find something to keep living for. Dimitri also shares a bit of how he felt when he lost his family too and how it gave him the will the go on living. Before he leaves Byleth alone, he assures Byleth that he intends to stand by their side no matter what happens. Later on when Byleth finally comes outside, Dimitri will be glad to see them. However, remembering the injustice of Jeralt's death, he tells Byleth that he would kill anyone if they ask him of it.

The whereabouts of Jeralt's killers are found and Byleth is determined to avenge their father. Dimitri gladly offers to help. Byleth chases after Kronya who retreats further into the forest. There, Solon banishes Byleth into the darkness. The students are shocked to see their Professor disappear. Dimitri is enraged at what Solon had done to Byleth and becomes ruthless. Byleth fuses with Sothis and returns to defeat Solon. After the battle, Dimitri is relieved that Byleth is not hurt. Byleth faints from exhaustion and Dimitri carries them back. The last thread of Dimitri's sanity snaps when the Flame Emperor is unmasked and revealed to be Edelgard. As Dimitri approaches Edelgard and her forces, Byleth is visibly worried and attempts to stop Dimitri from killing his stepsister but he shoves their hand away. Outraged over Edelgard's perceived involvement in his family's death, Dimitri snaps and slaughters her remaining forces forcing her to retreat.

Edelgard ascends the Adrestian Empire's throne and declares war on the Church of Seiros. Dimitri fights beside Claude in the front lines to protect the Monastery from invasion. Although Edelgard and her vanguard are repelled, the invaders are reinforced by a larger army, forcing Rhea to enter the fray as The Immaculate One. Byleth attempts to aid her, but Thales sends them plummeting into a ravine. Garegg Mach falls. Byleth goes missingfor five years.

Time Skip: Azure Moon
The disappearance of Byleth and Dedue's apparent sacrifice further deranged Dimitri's already crumbled sanity. After he escapes his execution in Fhirdiad, he lives a solitary life as a vagabond. Rumors of a sadistic warrior capable of slaying scores of soldiers begin to propagate throughout the Empire. Byleth is awoken by Sothis and returns to the monastery in hopes of reuniting with their students. In the Goddess tower, Byleth stumbles upon corpses of imperial soldiers and finds Dimitri, now a shell of his former self, alone in the ruins of the Monastery. Byleth walks over to him and reaches for his hand but he looks away and refuses to reach back. He mistakes Byleth for a ghost but realizes that they are alive.

Byleth and Dimitri eventually reunite with the rest of the Blue Lions along with the Knights of Seiros. Dimitri immediately plans on killing Edelgard by mobilizing his allies. With Byleth as the acting leader of the church of Seiros, together, they intend to stop Edelgard's conquest.

With Dimitri at his worst moments, Byleth continues to aid him and never gives up on him just as their allies hope that they can bring him back to his senses. Some time after Rodrigue's sacrifice, a devastated Dimitri attempts to set out for Enbarr but Byleth stops him. Dimitri despairs at how its pointless to move on for the sake of the dead to which Byleth reminds him that he should live for what he believes in instead. As a heavy downpour begins to fall, Byleth offers their hand to Dimitri and this time, Dimitri finally accepts their hand noting how warm it is. Dimitri begins to question what he is really fighting for and begins to apologize to everyone for his foolishness and to atone for his sins. Byleth and The Blue lions then continue to fight alongside him.

Byleth helps Dimitri reclaim the kingdom and save his people from Cornelia's tyranny. With Byleth's insistence that he face his people, Dimitri with Byleth and Gilbert at his side, reluctantly walks out onto the castle balcony to find the people of Faerghus cheering his return. Dimitri takes his rightful place as King of Faerghus. After reclaiming the capital, a celebration was held. Dimitri finds Byleth outside and asks if they have worn out from the festivities. He confides in Byleth that he was always afraid of going near the graves of his loved ones but now he knows that he should't stay away forever. He thanks Byleth for teaching him how to live. He would have died a fruitless death in battle if Byleth wasn't there with him.

Dimitri is devastated to know of his stepmother, Patricia's likely involvement in the tragedy of Duscur. Byleth finds him in the Cathedral at night, pondering over the revelation about Patricia. Dimitri tells Byleth that even if his stepmother never loved him, he is not to be pitied as he has dear friends and allies who cares for him and now, he has Byleth by his side. After Dimitri defeats a transformed Edelgard in battle, he attempts to reconcile with his stepsister. Byleth smiles at the sight of the two until Edelgard throws the dagger to his shoulder prompting him to kill her. Dimitri and Byleth walks away from the throne room but as they are about to step outside, Dimitri stops and tries to look back but Byleth grabs his hand with a pleading expression. They then walk out of the throne room together with the people cheering outside.

Post-War
Dimitri is crowned king and Byleth becomes the new archbishop. Their marriage gave the people of fodlan much to celebrate. As leaders of the church and state respectively, they devoted themselves to improving life for the people. Because of their positions, at times, the two engaged in heated debate. but even still, when enjoying a long horse ride or spending a quiet evening together, they were not as the world saw them but rather two adoring spouses who were desperately in love and they remained that way for the rest of their days.

Moments

 * In Chapter 6: Rumors of a Reaper, Byleth smiles genuinely for the first time and if Byleth repeats the same expression as Dimitri asks of them, his support points will go up and he will call it mesmerizing.
 * After winning the battle of the Eagle and the Lion, Dimitri tells Byleth that he loves seeing them happy like this and that the look on their face may be the best boon of the day.
 * In Sothis' Paralogue, Tales of the Red Canyon, Dimitri is the only lord who scolds Byleth for venturing into the canyon alone while most of the characters took it as good battle experience.
 * Dimitri is the only character who invites Byleth directly to the Goddess tower.
 * In the goddess tower event, Dimitri asks Byleth if they should wish "that we'll be together forever". There's a moment of silence of since Byleth gives Dimitri a questioning look. To break the silence, he plays it off as a joke to Byleth's disappointment regardless of the response chosen. He apologizes to Byleth and tells her he isn't even sure if he can really "have a future to promise to someone".
 * In Chapter 10: Where the Goddess Dwells, Dimitri is the only lord who will carry Byleth back to camp regardless of their gender. If Byleth is female, Dimitri will first apologize before carrying her.
 * Dimitri is the only lord who immediately comes to see Byleth after Jeralt's death. In other routes, Alois comes to see Byleth first.
 * As thanks for helping Dimitri teach swordsmanship to the children, he offers to take Byleth to dinner.
 * In the time skip, tea time is held in Byleth's room. One of Dimitri's unique tea time dialogue, is him telling Byleth that he would invite them to his quarters next but his room is "too bare". He also notes how he feels comfortable it is in Byleth's room
 * In his tea time dialogue during pre time skip, he chats about how he loves going for a long horse ride on his own. His ending with Byleth, where they spend time together going for a long horse ride is the only other time it was ever mentioned.
 * Azure moon is the only ending mural in which Byleth is there beside the Lord.
 * "A place to rest" is the music that plays in majority of the S-supports. Dimitri is the only Lord in which the music for his S-support is "Somewhere to belong". This usually plays only on platonic S-Support. However, Hubert is also the other exception.
 * In Silver Snow, no matter who Byleth chooses of the three lords to be concerned about, it will always be Dimitri who will come to see Byleth to say goodbye. Whether it was his ghost or Byleth dreaming about him is unknown.

Fanon
The ship is one of the most popular romances of Fire Emblem Three houses. Although, Dimitri can only be romanced by female Byleth, Dimitri with male Byleth is also quite popular. Fans also sees that Dimitri and Byleth parallels Byleth's parents, Jeralt and Sitri.

Fandom
Fanfiction

Dimitri/Byleth tag on AO3

Twitter

Dimileth hashtag on twitter

Dimileth posts on twitter

Tumblr

Dimileth hashtag on Tumblr