KaiShin

KaiShin is the slash ship between Kuroba Kaito and Kudo Shinichi from the Detective Conan/Magic Kaito fandoms.

Canon
Kaito and Shinichi meet for the first time during the clock tower heist. During this heist, Kaito attempts to steal the hands of the clock, which are supposedly lined with diamonds. Throughout the course of the heist, Kaito struggles against the police force as they track his movements, something he usually doesn't have to deal with when he misdirects them. It is revealed that Shinichi is directing the police force from a helicopter circling the clock tower. As part of the heist, Kaito covers the face of the clock with a white sheet on which he projects a picture of the clock without hands. Shinichi discovers this and shoots at the screen form the helicopter. Before the two can lay eyes on each other, Kaito escapes into the crowd, but he notes this heist, with Shinichi's presence, is different from his other ones. While Shinichi, even after the that first meeting, don't catch the name of the thief attempted to steal the hands of the clock yet. Their next meeting would be the first time they meet face to face.

Their next meeting is after Shinichi is poisoned, and becomes Conan. The Black Star Heist, Is their chronological first meeting, being earlier in the show than the Clock Tower Heist. In this episode, Kaito attempts to steal the Black Star, a pearl owned by the Suzuki Family. Conan, Currently living with the Mouri Family, Is invited to try and stop Kaito from stealing the Jewel, as his guardian, Mouri Kogoro, is a famous "detective". Conan manages to figure out where Kaito is, and confront him, setting off a firework in order to alert the police to his location. Kaito manages to escape though. He leaves a note stating that this was just a practice run, and that he will return to steal the pearl on a ship carrying the Black Star. When the day comes for Kaito to attempt to steal the gem again, He manages to get the upper hand to Conan, by disguising as his childhood friend, Mouri Ran, and when he's figured out, stating that he left her tied up naked in a boat.

Fanon
Kaishin is the most popular ship within the fandom. On AO3, Kaishin is the most written ship for both characters, and for both the Detective Conan and Magic Kaito tags. ShinRan, CoAi, and Kuroba Kaito/Nakamori Aoko are notable rival ships for Kaishin.

There are over 2,800 works for Kaishin on AO3.

Fandom
FAN FICTION

Trivia
 * Kaito and Shinichi are Canonically almost identical, They also share a voice actor (Kappei Yamaguchi)
 * Shinichi's mother trained in the art of disguise under Kaito's Father, and their families were friends. It's never stated if they had met before the events of the series still.
 * Kaito and Shinichi's voice actor has made an unofficial video about Kaito kissing Shinchi.
 * While it is only implied in the Manga that Kaito knows Conan's true identity, He outright states it in the movies
 * Kaito has helped Shinichi by disguise as him when Shinichi almost told Ran that Conan and him are the same person, in repay to Shinichi helping one of Kaito's injured dove.