The author considers \(G_2\)-cobordisms between 6-manifolds with \(\operatorname{SL}(3,\mathbb{C})\)-structures. Let \(X\) be a spin 6-manifold and let \(\psi_1\) and \(\psi_2\) be closed definite 3-forms that yield \(\operatorname{SL}(3,\mathbb{C})\)-structures on \(X\). The forms \(\psi_1\) and \(\psi_2\) are \(G_2\)-cobordant if there exists a closed definite 3-form \(\phi\) defining a \(G_2\)-structure on \(X\times [t_1,t_2]\) compatible with the orientation and whose restrictions on \(X\times \{t_i\}\) coincide with \(\psi_i\), \(i=1,2\). This yields a binary relation on the set of all closed definite 3-forms on \(X\). The author is interested in some properties of these binary relation. In particular, the question of the irreflectiveness of this relation is discussed. One of the results (Theorem 15) shows that under extra assumption of the \(\operatorname{SO}(3)\)-invariance, the relation is not reflexive.