It is to the left, not right, Gyro precesion applies to all rotation mass, when the plane of rotation is disturbed the applied force will act 90 degrees on the rotation orientation, when the tail lift, you can assume you are pushing the propeller disc from behind the top of the disc and 90 degrees will cause to yaw to the left as you are actually pushing the propeller disc from behind the right hand side. This is why the contra cancel the yaw as both propellers push or pull from both sides.