How exactly DID Spamton and Tenna know each other?

The two of them are from two different dark worlds, and from my understanding I thought darkners were given life by the dark fountains, which is when they become characters. If they knew each other before, then by my understanding that must mean they were in a dark world together at some point, because im not certain if relationships between darkners can develop while they aren’t “alive”(aka inanimate objects in the light world). So how exactly did those two get to know each other? Do they turn back into darkners when we aren’t looking like in Toy Story?

Plus, how would they have known each other in the first place? Tenna is a CRT and Spamton is spam mail, unless he was something like spam calls or physical mail before I don’t see how they are exactly related. (and even with those examples they still aren’t really that related)

(reuploading because reddit is buggy and wasn’t letting me see comments)