Light unit for use in vehicle that leans into turns, method for adjusting the same, vehicle that leans into turns, and method for adjusting the same

A light unit (100) for use in a vehicle (10) that leans into turns includes: a fixed part (101) fixed to a vehicle body that is allowed to lean while the vehicle (10) is running; a sub headlight (130) provided in the fixed part (101) and including a sub headlight light source (131), the sub headlight (130) being configured to produce a cut-off line at the upper side of light emitted from the sub headlight light source (131), the cut-off line extending obliquely when the vehicle body is upright, the sub headlight (130) being configured to be turned on in accordance with a lean angle of the vehicle (10) while the vehicle is running; a sub headlight turn-on device (150) for a vehicle's stopped state configured to turn on the sub headlight (130) when the vehicle (10) is stopped; and a sub-headlight cut-off line moving device (140) configured to, when the vehicle (10) is stopped, move the cut-off line of the light emitted from the sub headlight (130) under a state where the sub headlight (130) is turned on and the fixed part (101) is fixed to the vehicle body.