*MGS1 spoilers*
If you give in to the torture, Meryl dies, and Snake flies off into space with Otacon.
Okay, that part about space isn't true, but they do make a Space Odyssey reference with the fact that their names are Hal and Dave. But it's mostly the same, except for swapping Meryl with Otacon, and Snake has an emotional moment about not being able to save her.
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