Kaimark

Kaimark is the slash ship between Kai and Mark Lee from the SuperM fandom.

Canon
Kai and Mark are labelmates under SM Entertainment. Kai is a member of EXO, and Mark is from NCT. Mark is seen several times fanboying over EXO and has great respect for the group.

They performed at several SMTown concerts together and were seen nearby each other. Both groups have also had collaboration stages with each other, including a performance of Monster by NCT and EXO at the 2018 KBS Song Festival. It is probable that they had some interactions since they are both idols under the same label, but little of their interactions have been caught on camera, until their debut in SuperM.

In late 2019, Kai and Mark debuted as members of SuperM. Dubbed as the "Avengers of K-Pop", the group consists of idols from different SM boygroups, namely EXO, NCT, WayV, and SHINee.

Fanon
Prior to the debut of SuperM, the ship had little to no popularity, though both Mark and Kai were popular idols under SM Entertainment with huge established fanbases. Kaimark started quick popularity after SuperM's debut, especially after the press conference, where Kai and Mark were shown to be good friends.

Fandom
AO3