  We discuss herein the emergence of a large entropy change in metallic
Li0.33VS2 derived from the orbitally assisted loose {\sigma} bond formation.
Comprehensive structural studies based on synchrotron x-ray and neutron
diffraction analyses clarify the fabrication of ribbon chains at 375 K,
consisting of multiple three-centered two-electron {\sigma} bonds based on the
viewpoint of local chemical bonding. Although the metallic conductivity
persists down to the lowest temperature measured, exceptionally large entropy
change as a metal, as much as {\Delta}S = 6.6 J/mol K, appears at the
transition. Emergence of a large entropy change in a metallic state expects us
the possible novel functional materials, such as a heat-storage material with
rapid thermal response.
