Lilin are the offspring of an Infernal and any other Non-magical race. Unlike Nephilim, they are more common, but also more reviled. They own is much in the same way their Infernal acestors do; some lean into the tropes while other simply try not to be noticed and keep their heads down.
Much like their Infernal accestors, Lilin can be very single-minded, specially when it comes to someone they have interest in. It's not fair to say they're jealous or clingy, rather they are devoted and loyal to those special to them.
Much like Nephilim, Lilin appear primarily as whatever the secondary race they are. There is one major exception: all Lilin are born with some Infernal trait. It's generally small, such as a horn or the hint of wings, or even just eye or skin color. This trait is often explained away by parents desperate to have a normal child. For most, over time, whatever the trait is will disapear, as the child learns subconsciously to suppress their default form.
Lilin also have a 'default form', but it's rarely a perfected version of themselves, and more often what they fear to become. These forms are almost always very Infernal in appearance. Some have tails (like Succubi) or wings or both. Very commonly, Lilin eyes glow and are often red, purple, orange or bright blue. Most often also have black sclera in their default form.
Lilin have a unique trait that whenever they use their abilities, they have a tendency to reveal their default form, or a portion of it. The more power they use, the more likely it is that their body will revert to it's default form.
Lilin function the same as Nephilim in this regard; Lilin power their magical abilities with the Living Force of themselves and those around them. They can choose to drain the Living Force much the same way a monster can, however they do not feel the same monsterous hunger for Living Force. Also like Nephilim, they have a maximum amount of magic they can store. Over time, this can be trained to be greatly increased.
Lilin can fly just like Nephilim, but they often don't bother. It takes so much energy and effort most see it as a waste when there's so much else they could do with their power.
Lilin are, often, master shape-shifters. They have the same limitations as Nephilim: i.e. they can only take other humanoid shapes near their own. An elven Lilin could take the form of a Human or and Elf or an Orc easily. However, they would have to be a short Dragonborn and could never take the form of a Dragon proper.
Shape-shifting comes very natrually to Lilin, but it takes them years to master. Most Lilin are aware of what they are the moment they find themselves starting to change minor aspects of themselves without thought. Pretty quickly thereafter they start to play with their abilites, and they work out just who and what they are.
Note: Infernals will often be on the look out for Lilin who are only just discovering themselves and offer guidance until the Lilin gets on their feet. It's more a mentorship; Infernal parents tend to stick around as much as possible when they directly sire a Lilin, so the child would grow up knowing what they are. It's the ones who come about because of ancestry asserting itself that the Infernals look for. They are not nearly as hands-off as their Celestial kin are with the Nephilim. That being said, they will only stick around long enough for the Lilin to get the basics; they believe the best way to learn is by doing, so the let their newfound kin do.
Lilin do not revert to their default form when unconscious, unless they are also completely drained. They will remain in whatever form they were last in until they either consciously change, or they are drained of all of their magic.
However, when exerting themselves, a Lilin's default form wants to assert itself and they often struggle to suppress it. If they're using a lot of magic energy, they simply loose the ability to control their form and they revert to their default form.
As masters of shape-shifting, Lilin are able to access the Infernal ability to change other's form. This ability works just like an Infernals, except they are limited by the same limitations as their own shape-shifting ability, i.e. they can only take other humanoid shapes near the target's own.
Lilin can live a long time. They generally believe themselves to be immortal like their Infernal kin, however enough have died of old age to bring this into question. They are still fully immune to disease and posion like Infernals.
Lilin who have access to powerful magic items, or areas of magic (such as being near monsters) seem able to extend their lives to at least as long as Dragonborn, if not more.
Lilin also have the unique ability to extend the life of those who spend a great deal of time around them. This seems to be an extension of their ability to polymorph others, and is often just limited to those they are very emotionally close to.
Lilin limitations are pretty much the same as Nephilim. While they are not any less effected by their personal beliefs, they are, in general, more aware of these limitations and aren't trying to hold themselves up to the image of ancient heros. This goes both ways, however, as they also do not tend to try to push themselves past their limits, meaning on the whole Lilin tend to be less powerful than Nephilim.
Lilin have tended to make a point to avoid being in the public eye. Because of the negative view of Infernals, Lilin naturally try to hide their nature. Most end up becoming nomatic loners, as it's easier to avoid people finding out your secret if you move around much.
Lilin are greeted with a chilly response at best, outright hostility at worst. There's a general belief that they are untrustworthy and evil, though very few stories of "evil" Lilin exist.
You can never trust them, they might mean well but their Infernal blood twists everything they try to do. They're cursed.
I hesitate to brand an entire race, but Lilin are the products of their parentage, make no mistake. I would hesitate before having any dealings with them, no matter the cricumstances.
An ill omen, should one cross your path. Look, I know what I sad about Infernals, but Lilin are just... unfortunate. They have all the worst traits of their kin, and none of the fun ones.
Ever Lilin I've met has treated me and mine with respect, and simply wanted to be left alone. So I did. I never bothered them long enough to form an opinion.
I have a very dear friend who is a Lilin. They are one of the best people I know. While I'm sure not all are as good or loyal, I've never seen a reason to believe the popular take. They are a race, like any other, neither good nor bad.
While, in general, the magical races tend to have a better opinion of Lilin, very few have interactions with them, since Lilin very rarely make their way to the Magic Realm.
These kin are strong, respectful, and highly independant. It's hard to judge if this is wisdom or simply necessity.
They are more tolerable than their Infernal parents, at least. Beyond that, they seem to be determined to not be of any importance.
Our children are something else. They're learning, they're growing, and they don't let anything get them down. Give them another few centuries and they'll really surprize you.
We have not encountered one, yet, thought from the opinions on the others we should rectify that, soon.