Basic Trope: Two characters who survive a harrowing ordeal together have sex to celebrate being alive.
Straight: Bob and Alice have sex after surviving a battle with Emperor Evulz.
Exaggerated: Bob and Alice have sex after any incident that is even vaguely stressful.
Alice & Bob celebrate surviving the battle with a passionate make-out session.
Alice and Bob got into a fight with Jay which could have easily gotten them injured & celebrate not getting injured with sex.
Justified: Bob and Alice have had feeling for each other for quite some time. Coming so close to dying against Emperor Evulz made them realise that life was too short not to let such feelings go unsaid, and so they acted on them and became lovers.
Defied: Alice and Bob refrain from having sex because of their moral and religious convictions (or just because this is the worst possible time and place to do it), despite wanting each other badly.
Discussed: "And then you had sex with her?"
Conversed: "Gee, if I were in a situation like theirs, I wouldn't be able to stop myself, either."
Deconstructed: Alice and Bob have sex after defeating Emperor Evulz, but because they had sex in the heat of the moment with no forethought, it puts a strain on their relationship and Alice must cope with an unwanted pregnancy.
Reconstructed: Alice and Bob bring condoms to every battle now.
Played for Laughs: Immediately after defeating Emperor Evulz, Bob and Alice have sex on the spot, in the Emperor's throne room. Bonus points if Drake and/or Lance walk in on them and one of them says "Now thats what I call a happy ending."