Gyneflexible

Gineflexible or Gyneflexible is a term for a person who is mostly attracted to women, but very occasionally can feel attraction toward men. The inverse of Androflexible.

Alternatively, it can also mean someone is mostly attracted towards femininity, but very occasionally can feel attraction towards masculinity.

A second explanation (Might be the same-ish) would be basically like abrosexual but only with the sexualities Gynesexual and (maybe) Androsexual.