A totally fictitious example: Consider a distant object that is at rest in an inertial frame. In that frame you rotate at some uniform angular velocity. In your non-inertial rest frame, the object is rotating at the opposite angular velocity, it thus has a centripetal acceleration toward you. How then do we account for the fictitious centripetal force acting on the object? There is a centrifugal force due to using a non-inertial frame, but this force acts in the opposite direction, it is directed radially outward. However, there is another fictitious force acting on the object, the Coriolis force which has twice the magnitude of the centrifugal force. So, in this case, the fictitious centripetal force is the sum of the centrifugal and the Coriolis force.

A totally fictitious example: Consider a distant object that is at rest in an inertial frame. In that frame you rotate at some uniform angular velocity. In your non-inertial rest frame, the object is rotating at the opposite angular velocity, it thus has a centripetal acceleration toward you. How then do we account for the fictitious centripetal force acting on the object? There is a centrifugal force due to using a non-inertial frame, but this force acts in the opposite direction, it is directed radially outward. However, there is another fictitious force acting on the object, the Coriolis force which has twice the magnitude of the centrifugal force and this is directed radially inwards (in this particular case). So, in this case, the fictitious centripetal force is the sum of the centrifugal and the Coriolis force.