Whereas humans seem to classify sexuality relative to their own gender, Silirw classify it in absolute terms.

A human would say that Narus's sexuality is "heterosexual," but he would see his sexuality is "to-female."
A human would likewise say that Obict's sexuality is "heterosexual," but she would see her sexuality is "to-male."
Since Cyrals have 2 sexes, there are only 3 primary sexualities:  to-female, to-male, and to-female-and-male-likewise(bisexual).  Naturally, biology and sexuality are not so simple as that, but this system works well enough.  In any case, Narus and obict would consider each other to have DIFFERENT sexual orientations, but on Earth they would be considered to have the same.

Since Enials have males, females, AND hermaphrodites, it gets slightly more complex.  On top of those three already mentioned, they have to-hermaphrodite, to-male-and-hermaphrodite-likewise, to-female-and-hermaphrodite-likewise, and to-female-male-and-hermaphrodite-likewise(trisexual).  Anciu would be lattermost of these.  
Ymog would be to-female-and-hermaphrodite-likewise.  That one has 2 subcategories, standard and +.  Ymog does not fit into +, meaning he feels attraction to hermaphrodites, but not the masculine aspects of them.  The orientation to-male-and-hermaphrodite-likewise has similar subcategories, but of course in that case those who are not in the + subcategory do not feel attracted to the feminine aspects of hermaphrodites.  
Do remember that hermaphrodites have their own distinctions separate from those of males and females when considering this.

There are further, less common classifications for Enials (and Cyrals, but I'm not going to bother with those).
To-hermaphrodite-feminine describes the position of someone who likes hermaphrodites specifically for their feminine aspects, but not their hermaphrodite-specific aspects, and does not feel attracted to females.  To-hermaphrodite-masculine is similar.  To-hermaphrodite+ is the position of someone who likes the masculine and/or the feminine aspects of hermaphrodites, in addition to the aspects that are hermaphrodite-specific.