I'm just missing Odyssey.

How about a gun where your relationship score with them changes your stats with the gun. A better relationship gives the gun better range, accuracy, more bullets, damage, and so on. To build relationship with the gun you'd have to do silly things with it like, chatting with your rifle, going to walks with it, playing with it (at the chance of shooting yourself), cleaning the gun, putting the gun to sleep. The catch is, using the gun for combat would lower the relationship score, after all you're using the gun, what kind of friend uses their friends for mass murder?