It is often used hyperbolically (which means "in an exaggerated fashion"). So, Bark's example is appropriate. Although not definitive. Lox defines it nicely and comprehensively. There is one good literal use of it, though (the koala in your photo looks like someone just said this to them): Life. No-one gets out alive.

when two people are alive after a long kissing session

What you explained seems to be suitable for the situation I've read in the fiction. Thank you.

to escape from a deadly situation without being killed. Often used metaphorically to mean, getting out of a bad situation unharmed.