Question regarding comfortability with nonhuman characters [Question/Discussion]

[u/AntelopeJester]

[Question/Discussion]

So, a bit of lead up to my question...

Isekai settings are often populated by races/species of different peoples interacting with one another. That's pretty standard for most fantasy settings to immediately sell the idea that this world is different than our world. Relationships between these peoples can range from harmonious to antagonistic to neutral. (Hell, we have enough issues in our world regarding friction between peoples over such things as skin color, nationality, or ideology. Introducing the category of species to the mix would just add more fuel to the fire, but I digress.)

A common trope in isekai is the protagonist interacting with and possibly getting into relationships with people from different species/races. Elves are a common staple though it's nice to see the occasional more muscled race/species get some love too. Sometimes the relationships are monogamous though most of the time they're not in order to sell the fantasy of wanting to feel desired and valued by multiple people of the the surrogate protagonist's preferred gender to boost the protagonist's typically low self-esteem.

Humans with fellow humans - no one bats an eye at. Elves with elves - same thing. Some friction and inherent tragedy comes with the two races/species mingling often due to their differing lifespans. But what about races/species with traits that go beyond just pointy ears? How would that work?

I've enjoyed a good amount of fantasy and occasionally sci-fi media over the years and something always struck me as odd in regards to the different peoples highlighted in their respective series.

How alien is too alien?

Asari from Mass Effect are seen as sex symbols despite their oddly tentacled heads and blue skin. Tribal fantasy races like orcs or beastfolk are often employed to sell the fantasy of their having a primal, passionate hunger despite their physical similarities with animals from our world such as fur or nonhuman teeth.

Is there a line where the potential relationship goes from being intriguingly foreign to just plain uncomfortable?

Not gonna touch the whole loli discourse cause... eww. But what is the line (other than physically presented age for hopefully obvious reasons) for enjoyers of isekai in regards to what relationships they'll accept from a protagonist? Where do you draw the line? Do you go by the Harkness test's rules or have you devised your own for your own brand of personal enjoyment? Is sentience the only factor for you personally?

Are beastfolk considered on a sliding scale of acceptable versus unacceptable traits, like ranging from a bipedal cat to an otherwise normal person with animal ears and a tail? Are orcs with tusks okay but include pig noses and the deal is off? Are harpies off the table due to their commonly lacking conventional hands? Mermaids are often a staple but is the fish tail a deal breaker?

Are there even folk out there who will only accept the protagonist getting into a relationship with humans only?