ShapeSpook

ShapeSpook is the femslash ship between Spooky Spoon and the Shape Japer from the Numberjacks fandom.

Canon
They do not speak directly to each other on-screen during the show, but it is implied that they do/have done. They share two episodes (Counting Down to Christmas and Seaside Adventure) In the same episodes, it is also shown that they are canonically friends.

In Counting Down to Christmas, they are seen causing trouble together as Spooky makes the spoons 'dance' and Japer changes the size of things. In Seaside Adventure, their scenes are completely separate apart from when all of the Meanies are together in the 'final battle' scene. Most interpretations of their relationship is up to the shippers to piece together the very little evidence within the show.

Fanon
It is unknown when the ship became popular within the fandom, but is the most popular MeaniexMeanie ship. There have been debates as to if they see each other as sisters, friends or even lovers, but since they are not canonically siblings most people don't mind the ship.

A lot of users, including those who don't ship ShapeSpook, see the two as being very close friends - often them being described as such since they are 'the only ones of their kind'. This fuels the ship's popularity as more people begin to notice their similarities and how cute of a ship it would be.

Fandom
Most fanart appears on Reddit, but some on Tumblr aswell. There are several ask responses from Ask-Numberjacks featuring the two, and even though they are not stated to be romantic scenes, some users have interpreted them as such.

Trivia

 * They do not speak to each other at all on screen in the show.
 * They are the main two Meanies in Counting Down to Christmas.
 * They are the only two female Meanies in the show.
 * They are canonically friends.
 * Both also share a voice actress - Rachel Preece (and OneCrowMurder in web-series Mega Mathematics Madness)