Ikesoren

Ikesoren is the slash ship between Ike Fire Emblem and, as the name already implies, Soren Fire Emblem from the Fire Emblem franchise.

Canon
Ike and Soren are both playable characters in Fire Emblem: Path of Radiance and Fire Emblem: Radiant Dawn. Soren clearly harbors an unconditional gaydoration towards Ike which is quite noticeable throughout both Fire Emblem: Path of Radiance and Fire Emblem: Radiant Dawn. Likewise, Ike Fire Emblem responds rather well to Soren's affections, always making sure he is doing well, as well as lending him emotional support whenever he needs it, clearly worrying about him throughout the narrative. It also is worth mentioning that throughout the entirety of the narrative, Ike refuses to romantically involve himself with women and rejects every single female advance toward him throughout the games. [Spoilers!] At the end of Radiant Dawn, should the player decide to raise their support level to A and thus unlock their strong gay energies, they will have a quite riveting moment of true broship together, embracing each other lovingly in raw brotherly comradeship, with Soren saying “There’s only one place for me to be, Ike… and it’s by your side.” The official art of book Fire Emblem: Radiant Dawn Memorial Book Tellius Recollection: The Second Volume (2016) further backs this up, with volume 2 stating that Ike feels love for Soren (p. 87). I mean heck, they even got featured at an LGBT gaming exhibit in a museum in Berlin. Furthermore, their interactions are said to have been heavily watered down in the translated version of the games, which already reads as being pretty gay, whereas in the Japanese ones, their love is much more apparent.

Fanon
Ikesoren is one of the most popular, if not the most popular Path of Radiance/Radiant Dawn-related ship, with the fandom regularly churning out all kinds of fanart as well as fanfiction. It has a vast backing due to being heavily implied as canon in the source material as well as the art of book Fire Emblem: Radiant Dawn Memorial Book Tellius Recollection: The Second Volume (2016), however it is also known to receive a lot of hate, especially by those known as the Priam Existers, an exotic species of exceptionally smart Youtube commenters who have clearly digested the source material in a factual and logical manner.

Fandom
The fandom is heavily involved with this ship and has come up with loads of different takes and AUs for it.
 * Ikesoren posts on Tumblr
 * Ikesoren group on Deviantart

Trivia

 * Ike and Soren were featured at an LGBT gaming exhibit in a museum in Berlin
 * Ike and Soren have their own Cipher card
 * Ike and Soren have matching Valentines alts in the mobile game Fire Emblem: Heroes 
 * Soren's Novice class support spirit in Super Smash Bros.: Ultimate comes with an Ike