Marine propulsion device and marine vessel

A marine vessel comprising:

• a hull;
• and
• a marine propulsion device attached to the hull;
• wherein
• the marine propulsion device includes:
• a propeller;
• an electric motor to drive the propeller;
• a motor controller configured or programmed to control driving of the electric motor;
• a case to house the motor controller;
• a steering mechanism to integrally rotate the propeller, the electric motor, and the case in a right-left direction;
• and
• two power lines including first ends connected to the motor controller, and including positive and negative lines to supply driving electric power to the motor controller;
• the two power lines are twisted together inside at least the case so as to absorb twisting of the two power lines during rotation by the steering mechanism;
• the case includes an upper case and a lower case below the upper case to house the motor controller;
• the steering mechanism is operable to integrally rotate the propeller, the electric motor, and the lower case in the right-left direction with respect to the upper case;
• the two power lines include upper ends of twisted portions inside the upper case, and lower ends of the twisted portions inside the lower case;
• and
• the marine propulsion device further includes:
• an upper restrainer to bundle and restrain the upper ends of the twisted portions of the two power lines within the upper case;
• and
• a lower restrainer to bundle and restrain the lower ends of the twisted portions of the two power lines within the lower case.