South West (Nairutya) the name itself suggests the demon in it. The North East direction is the direction of the Gods whereas the South West direction is that of the demons.Two diverse aspects are continuously challenging each other from the beginning of Creation such as God – Demon; Good – Bad; Male – Female; Day – Night; Success – Failure; Fame – Disgrace and others. Due to the existence of negative aspects one is able to appreciate the positive and vice versa.
The Demon Nairuti is the ruler of this direction. His city is known as 'Krishnang' and is synonymous to darkness. His vehicle is human being and therefore the human race is constantly in the grip of problems and demonic forces. These problems ultimately give the strength to develop the fighting spirit in individuals. South West is the region of the Earth element that is heaviness and is the right choice for the master bed room for the family head.
The intensity of the Infra Red Rays is very high in the light of the afternoon Sun that is moving towards sunset. This is harmful for human beings. Hence, this region should have minimum doors and windows. It should also have extra thick walls , big trees with dense foliage and minimum open space which will obstruct the high intensity infra red rays from entering the vastu.