1a. You’re always plotting to prank each other (for example, by pretending you’re going to tell your partner a secret and then burping in his ear instead). True love requires knowing exactly how far you can push someone before they stab you in the face.
1b. You took it too far and got stabbed in the face, but you forgave each other and now you know exactly where the line is. Win-win.
2. You don’t keep secrets from each other, and you don’t have to because you have nothing to hide. Except a corpse.
3. You don’t mind doing favors for each other, like washing dishes that aren’t yours, or helping to hide the body. But not by throwing it in a river because it’s bound to wash up somewhere, but you can’t really bury it either because SOMEONE doesn’t want to get blood on their gardening shovel so you’re probably going to have to burn it but where the hell are you going to be able to do that inconspicuously? And anyways it hasn’t rained in weeks and you don’t want to start a freaking forest fire here, because at least ONE of us has got to be concerned about the earth, you know. For the children.
4a. You’re past the phase where you can’t stop thinking about each other all the time, and the phase where you can’t stop boning each other all the time, but you haven’t reached the phase where one of you has really gotten fat. You’re in a golden age of skinny contentedness.
4b. Alternatively, you ARE in the phase where one of you has really gotten fat, but the other one has developed a fetish for your love handles and all the dead-skin mildew that builds up under there.
5. Even though you may not find each other’s quirks adorable any more, you can pretty much tolerate all of them. Except for how he sometimes apparently murders people. Still, you’ve put on a lot of weight lately and you probably can’t do much better any more so you might as well let that one go.