Mystical Island Reboot

After the sinking of the yacht the main character finds herself on the shores of mystical Island with no memory of what happened. Trying to survive and find a way to call for help, the main character encounters a bound mysterious woman and brings her to his shelter. The main character reveals that she is on a forbidden island and together with that woman whom she named Sunday, the two of them go on a Mystical Island adventure together and discover his secrets.