You’ll be devoured by army ants, so sorry.
A lion. They always break your neck first, so you’d be dead before they start eating.
although a lion is still my first choice, there’s no guarantee you’ll be dead before they start eating.
[spoiler]video of a lion eating a rhino while it’s clearly still alive:
Not sure what's wrong with the rhino, but it's unable to effectively resist; all it can do is issue a weak protest with each bite.[/spoiler]I didn’t see a clear no on the cryptids, so I am going with SCP682. Getting murdered by a magic shape-shifting crocodile should be enough of a spectacle to distract me from the minute or two it takes to kill me.
Some will, others get squicked out just by the mere thought of it.
don’t think so, at least not easily. I mean it might manage to choke you down, but I think you’d get pretty chewed up before you got past its teeth and down its throat.
Yeah, but I’m probably significantly easier to kill than a rhino. Certainly my neck would seem more fragile.
I’m going with the Killer whale. I enjoy swimming, might as well die happy.
Drat.
This, for the same reason.
Hey, how about a big grouper? Could one of these monsters swallow an adult human whole?
The National Geographic fish book I had as a kid said that Giant Sea Bass, which I’m pretty sure are in the same family as groupers, has a “mouth that can take in a man.” I would think it would have a hard time getting an adult all the way down the hatch, though.
For those that chose this, if you are swallowed whole, then what are your final moments like inside the animal? Asphyxiate?
Assuming by “this” you mean consumed by an aquatic animal, then the answer is you hold your breath for as long as you can possibly stand it before you finally panic and try to breathe - and then you drown (there’s surely a fair bit of water in the animal’s stomach with you).
Rule 1:
“It must be an animal that exists today.”
Magical shape-shifting crocodiles do not exist. You shall be devoured by ants.
I was interested at first, then I read all the rules. Can’t even break the rules when dying - where’s the fun in that?
My answer to the OP would simply be “Surprise Me!”
Fine, whatever. Maybe I wanted to be devoured by ants! 
He’ll surprise you with army ants. He’s sadistic like that.
Fuck it, choosing is tantamount to acquiescing. Surprise me.
In fact:
If you’re so sorry, you take my place.
What’s he got against Navy, Air Force, Marine, or Coast Guard ants?