>>25274731Do you mean being digested as you're swallowed or instantaneous digestion once you're deposited in the stomach? The first would depend on whether you go in feet-first or head-first. Obviously head first would feel like instant death, but feet first would feel like loss of sensation creeping up you with every swallow, the nerves not having time to send signals to the brain, and then you'd die as your spine enters the stomach.
If instant digestion starts once you're fully inside, then it would feel like everything around you is stomach and then you'd be dead. Not much to it. Maybe the walls of the stomach would crush down upon you in a violent storm of acids and force, no time to react as you're destroyed and absorbed.