  A wide variety of higher-order symmetry protected topological phase(HOSPT)
with gapless corners or hinges had been proposed as a descendant of topological
crystalline insulator protected by spatial symmetry. In this work, we address a
new class of higher-order topological state which does not require crystalline
symmetries but instead relies on subsystem symmetry for protection. We propose
several strong interacting models with gapless hinge or corner based on a
`decorated hinge-wall condensate' picture. The hinge-wall, which appears as the
defect configuration of $Z_2$ paramagnet is decorated with lower-dim SPT state.
Such unique hinge-wall decoration structure leads to gapped surfaces separated
by gapless hinges. The non-trivial nature of the hinge modes can be captured by
a $1+1$D conformal field theory with a Wess-Zumino-Witten term. Besides, we
establish a no-go theorem to demonstrate the ungappable nature of the hinge by
making a connection between generalized Lieb-Schultz-Mattis theorem and the
boundary anomaly of HOSPT state. This universal correspondence engenders a
comprehensive criterion to determine the existence of HOSPT under certain
symmetry regardless of the microscopic Hamiltonian.
