"Who the heck are YOU?!"

There are dozens of object shows out there, each one in its own little universe, almost never touching each other. But what would happen if objects from one universe traveled to another?

*I've given a user who wishes to remain anonymous permission to crosspost this story to AO3. (Crossing Over got crossed over between websites, haha.) So if you find Crossing Over on AO3 posted by an anon, remember, it's NOT stolen!*

#1 in #inanimateinsanity - July 16th and December 10th 2020/March 19th and April 1st-19th 2021
#1 in #BFB - March 9th 2021