Romancezone

Romancezone (also known as lovezone, though this title isn't accurate) -- is a phenomenon of having romantical relationship with no hope of turning it into friendship or adoption.

Commonly considered as one of the most hideous things possible, right below lying and betraying.

Psychology and reasons
The evolutionary route of the Homelanders', along with genetical factors and other 'nature' side of 'nature vs nurture' have virtually no influence these cycles, thanks to the rapidly developing technologies.

Because of that, their psychological profiles have changed dramatically and cannot be considered as typical organic ones. For example, according to the Homelanders' classification, a species that has two or more sexes, formed by evolutionary development, cannot be considered truly sapient.

The major reason for such characteristic is a fact that they were not able to get rid of such primitive phenomenon that humiliates and belittles their society, cognition and the very idea of sapience.

It's logical that romance per se would be considered in a negative light, because it's based on the primary function of every living being -- a function of reproduction and survival.

The driving power of it, such as hormones and pheromones, reacts to every potential possibility that could lead to procreation, hence the idea of 'love at the first sight' exists. A person under the 'tyranny of biochemistry' can only estimate attractiveness and, less commonly, a possible potential of birthing healthy and competitive offsprings.

None of the aforementioned is accepted or even tolerated among the Homelanders, because the very definition of romance explicitly exclusives intelligence from equation, leading to cumbersome social constructs of marriage, courtship institution and many others, vainly designed to curb primitive interactions.

Another reason for such characteristic of romance is a fact that it either hinders or completely prevents the development of one of two true relationships between the Homelanders', leading to the robbery of the best possible experience any Homelander can ever have.

Shattered
A rarely occuring phenomenon, commonly known as a 'Shattered Homelander' or simply 'Shattered', means that a certain Homelander does not have any of the fundamental relationships. The rarity of its occurence had lead to a few false assumptions that romance could be an allowable alternative.

They were proven false with a vast scientific research, that revealed the future course of living of all Shattered. Turns out, each of them eventually starts a true relationship, rendering romance obsolete.

What's more, even before such research, none of the Shattered has ever had a romance, primarily due to a fact that it implies phasing out intelligence in favor of the 'tyranny of biochemistry'.

Alternatives
But even with all the data in mind, the Homelanders still needed relationships that could be a temporarily substitute of the fundamental relationships, even if a vastly inferior. Besides, even those who already had friendship or adoption needed a relationship that would definite their interactions with the Homelanders they knew and communicated well with.

A simple solution was to call such relationships 'contacts'. Meaning that even if two Homelanders didn't share either of true relationships, they still know each other well and can spend time together with a known, joyful and generally productive outcome.

What If...?
Some theories have arised recently, addressing a hypothetical scenario of the first contact with a sentient species which, among other things, raised a question about romance. In particular, what if such specie would have romance as the main relationship?

After several researches, the Homelanders have agreed on their actions in case of this hypothetical scenario. While this species could not be considered truly sapient and therefore, deemed as undesirable to establish a contact with, a single representative of such species could be potentially treated as a Homelander; particilary as a Shattered with no hope of having true relationships.

In such case, given their full consent and awareness of the obvious implications, a Shattered Homelanders can have romantic relationship with a representative of a sentient specie. Assuming, of course, the total control over an organic part of their brain, which is necessary to prevent the 'tyranny of biochemistry'.