The Smilodon Dopant also known by his true identity Mick is the pet of the Sonozaki Family, namely Ryubee Sonozaki. Unlike the other members of the family, Mick is more of a neutral character and only acts on Ryubee's orders, and goes into the ownership of the Narumi Detective Agency after Ryubee's death.
While normally appearing as a regular blue British Shorthair, Mick has shown to be more intelligent than the average house cat, appearing to know how to transform into his Dopant form and back. Out of all the Sonozaki Family members, Mick appears to favor Wakana Sonozaki, though will faithfully follow Ryubee's orders. Ryubee had Mick trained to go to a set location, when he moved a metal spoon back and forth three times, then pointed to that location. This was something Philip knew, leading to the Smilodon Dopant's defeat at the hands of Kamen Rider Double CycloneMetal, as Double used this trick with the Metal Shaft to have Mick sit calmly while he prepared his Maximum Drive.
Mick was named by the son of the Sonozaki Family, Raito (now known as Philip). He is often utilized by the Sonozaki Family to deal with matters outside their estate, such as hunting down Philip and traitors, as well as bodyguard and spy. While targeting Kyoko Todoroki, the Smilodon Dopant defeats Accel Trial before Double CycloneMetal catches the cat off guard before destroying his Gaia Driver and Smilodon Memory with the Metal Stag Break Maximum Drive. After Ryubee's death, Mick is adopted by the Narumi Agency for Philip. Shotaro is often shown buying him special cat food.
Through a Gaia Driver and the Smilodon Memory, Mick transforms into the humanoid Smilodon Dopant. The Dopant can discharge electricity and move fast enough to evade the homing shots of Kamen Rider Double LunaTrigger and outmaneuver Kamen Rider Accel Trial.
- Mick is the first Kamen Rider monster to have been an animal. All previous monsters and villains were either humans turned into monsters, or were already monsters.
- Mick is at least 12 years old since he was given to Raito at three.