The 1st house (Lagan) represents the physical body, the mind, and the core personality. Ketu is the planet of detachment, spirituality, and its physical representation in Lal Kitab is the Dog.
When Ketu sits in the 1st house, the person's core personality merges with the energy of Ketu. Dr. Rishi Rohit Sharma reveals a fascinating modern *Nishaniya*: This person will have an absolute obsession with dogs. They will know every single dog breed ("kutton ki breed sabhi jaanta hoga"), their temperaments, and their history.
They will prefer the company of dogs over humans, finding deep spiritual peace in their unconditional love.