* It's subtle, but ''Overkill'' has the relationship between Isaac and G. They start off on rocky terms--as an EstablishingCharacterMoment, Isaac's first words to G are "What's up, [[ClusterFBomb motherfucker]]?!" The first few chapters are punctuated with Isaac badmouthing G and G making snarky, sarcastic responses. But they slowly warm up to each other, working together to stop the mutant outbreak as well as avenge [[spoiler:the death of Isaac's father]], and by the final chapter, Isaac proudly proclaims that G's name "stands for 'genocide', motherfucker!" and G realizes that Isaac, underneath his macho exterior and constant foulmouthing of everyone, truly likes him as a friend. The final shot before the game ends is [[spoiler:the pilot of the rescue helicopter they're on being revealed to be a mutant, and what do Isaac and G do? [[AwesomeMoments They grab their guns and fire away, in unison.]]]]
* In the GoldenEnding of the ''1'', Rogan's fiance, [[DamselInDistress Sophie]], survives the attack by The Chariot. And if the existence of Lisa in the third game is any indication, [[EarnYourHappyEnding her survival is canon]].
* In the special addition for ''4'', after the end of each game there is a 'Partner Rating' to judge how well the two players cooperated with each other. If you managed to get a very high score, [[http://fc03.deviantart.net/fs70/f/2012/179/c/0/agent_g_x_kate_green_by_johnnytlad-d559o8h.jpg this]] will be the message that you get.
-->As long as there are couples like you in this world, there will always be hope for us all.