You were a human, but you died in a traffic accident involving a truck... You were excited to see what kind of place you'd be reincarnated in, but... to your surprise, the place you were sent to was the ocean.

You might wonder why, but it seems the god this time wasn't the 'isekai reincarnation' type, so you were simply tossed into the sea. Fortunately, your body is as it was before you died, and you've been made able to breathe underwater.