To be able to do so, we need more information.
In a cave ? because thats where they are in the movies and in real life.
Answer:
Henry Clerval
Explanation:
Victor took the remains of the creature he had worked on and rowed a boat out to drop them in the ocean. Then he fell asleep in the bottom of the boat. Upon finally reaching the shore, Victor found he was accused of a murder from the previous night. The group of townspeople took him to the magistrate, where he was called to see the body. It was Henry Clerval, Victor's childhood friend.