  Motivated by recent developments in Cosmology we would like to consider an
extension of the Ghost DE which we will call as varying Ghost DE. Ghost DE like
other models was introduced recently as a possible way to explain accelerated
expansion of the Universe. For the phenomenological origin of the varying Ghost
dark energy in our Universe we can suggest an existence of some unknown
dynamics between the Ghost Dark energy and a fluid which evaporated completely
making sense of the proposed effect. Moreover, we assume that this was in the
epochs and scales which are unreachable by nowadays experiments, like in very
early Universe. In this study we will investigate the model for cosmological
validity. We will apply observational and causality constraints to illuminate
physically correct behavior of the model from the phenomenological one. We saw
that an interaction between the varying Ghost DE and cold DM~(CDM) also
provides a solution to the cosmological coincidence problem. And we found that
the Ghost DE behaves as a matter like fluid in early Universe.
