Heteroflexible Flag
Heteroflexible is a sexuality and/or romantic orientation in which one is heterosexual/heteroromantic, but occasionally feels an attraction or is open to a relationship with the same gender.
Heteroflexibility is different than bisexual/biromantic; a bisexual/romantic person will always feel attraction to two genders (though they may have a preference), a heteroflexible person will only occasionally feel an attraction to the same gender or simply be open for a relationship.
The opposite of heteroflexible is homoflexible.