I think it is important to consider SX within the context of how sexuality may operate in a type. Of course, doesn't have to only do with a romantic relationship, can also be just this general...energy.

Anyways, Si/Ne types (I am sharing both Alpha and Delta since I feel like it could also overlap somewhat, what they are describing here):

Pseudo-Caregivers/Students: IEE (ENFp) EII (INFj)

These are types who exhibit paternal/maternal tendencies towards others in their everyday lives and may thus carry over these notions and temperaments into their romantic life. These types habitually attempt to give their partner what he/she "needs" (or what they believe they need). As a result, they may become drained by lack of attendance to their own needs and desires. In a partner, they are searching for a combination of strength and gentleness.


Teachers: LSE (ESTj) SLI (ISTp)


If I were to describe this type's approach to love, it would be "serious." He approaches his love interest almost with the intention to "teach." This can quite possibly rub the object of his affection in the wrong way, possibly interpreted as condescension. Like the childlike type, he may tend to live "outside sexuality" and may have to intellectualize it in order to be comfortable. He is looking for a worthy pupil.


Childlike Types: ENTp (ILE) INTj (LII)


These types seem to exist outside their own sexuality. Sex is to be metabolized psychologically for them in an almost roundabout way - as an emotional entity, or possibly even an intellectual exercise. In a partner, they are looking for someone who will deal with (and protect) their quirks and understand their sexuality on the same intellectual/emotional level.


Caregivers: ESE (ESFj) SEI (ISFp)


These are those types who openly express their need to "protect" and care for their romantic interest. In conversation may often lend a sympathetic ear (which, depending on the person, may be interpreted as insincerity, but it's exactly what the Child-like type is looking for). They are looking for someone who will not only accept their paternal/maternal tendencies, but welcome and thrive on it.
(X)

Also the different "types" of love:

Pragma (Te ego types)


"I love that we are useful together." Pragmatic lovers have a notion of being of service which they perceive to be rational and realistic. "I show my love by being useful". While they may be sincere about being useful themselves it also translates to also having expectations in a partner and of the relationship. Appreciates partners with compatible views and emotional stability. These traits are advantageous from practical point of view and, for example, can make reaching common or individual goals of the partners easier.

Storge (Fi ego types)


Like mania, this is emotional type of love, but it is all about stability. The attention is focused on static aspects. It values loyalties, responsibilities, duties and entitlements which promote long term stablity. Storge is often defined as familial love. There is a love between siblings, spouses, cousins, parents and children, but also between a married couple, who promise to extend, build their relationship and form a new stable bond of kinship. Just like family members, friends connected by this type of bond hold each other in good esteem to the outside world.



Philia (Ne ego types)


This type of love may be described as "friendship which brings pleasure". Partner treats the other one as very close friend. Partners usually like to play together, share a hobby, have similar interests and views or generally enjoy each other's characters. Physical aspect is strongly subdued and less important then understanding of each others ideas and giving freedom.

Eros (Si ego types)


Physical love that focuses on sensory pleasures. The feeling is intensified by positive aestetic attributes of the partner. Attention is focused on visual beauty, shapes, fragerence but also pleasant touch between various parts of the body. Focuses on the body. May become addicted to the physical presence of the partner. Likes closeness, knows how to caress and provide gentle sensual relaxation.
(X)

Based on the preferred functions for Delta.