Evolutionary prevalence of same-sex pairing is puzzling as it cannot result in direct reproduction. Especially, as the partner is different from regular heterosexual pairing, same-sex pairing must change their behavior for successful pair coordination. However, it remains unknown how and why animals retain such special case behaviors. Here we show that mating termites inherit bisexual behavioral repertoire for pair coordination, contributing to same-sex pair maintenance. Mating pairs of a termite, Reticulitermes speratus, show sexual dimorphic movements; female pauses while male moves to ensure the reunion upon accidental separation. We found this dimorphic movement even in same-sex pairing. One changed behavior from the regular heterosexual pairing to move like the other sex. Our data-based simulations confirmed that this context-dependent behavior enhances reunion rates. Furthermore, our phylogenetic analysis suggests that this behavioral plasticity is inherited from the ancestor that had no sex-specific role in pairing. Socio-environmental induction of ancestral behavioral potential is a key to successful same-sex pairing.