Your #1 fantasy, in one sentence.

[leo9]

Hmm..I'm sure I'll end up offending someone by this, but what the hell.
Find a girl, learn all of her hugest fears and terrors, capitalize on them and torment her for weeks, maybe months, amputate her legs and arms, beat her until she'd beg to die, and make her wait and wait for it until I'd decide to split her open.
Mmhm.

Hey, this is fantasy, right?

My late wife was suicidal when I first met her, and one of the ways I helped her get out of it was to make an agreement that if she decided once and for all that she wanted to die, I would arrange for her to "disappear" to somewhere undisturbed and spend a day or two doing all the things we fantasised about but couldn't risk doing, from breaking bones to spiked dildo fucking.

I still regret that by the time we realised she was terminal, there was no way I could get her out of the hospital to help her go the way she wanted - screaming in mingled orgasm and agony.