SX5s aren't just hopeless romantics
I feel like most SX5 descriptions tend to paint us as hopeless romantics desperate for true love, but to me, that reads more like a SO4.
In actuality, SX5s tend to look a lot more like SX7s because avarice, combined with the sexual instinct, compels the SX5 to merge with a higher ideal or cause that is typically beyond the scope of reality. Furthermore, as a SX5, some of my favorite artists are SX7s (i.e. Björk, Charli xcx, Grimes, Jane Remover, Kate Bush) because guiding their artistic expression is an emphasis on innovation and constant intellectual stimulation, which I deeply resonate with. In essence, SX5s are nonconformists. Their approach to intellectualism can be fairly bizarre, occult, and unsettling, but unlike SX7s, who can easily bounce from one idea to the next, SX5s are far more dogmatic and protective of their chosen idea or person.
In many ways, SX5 is a highly-intellectual character whose strange, lofty ideas can often transcend the SO5's ivory tower, but in addition to their ability to reach new intellectual heights, SX5s are earthly creatures who are far more in touch with their 8 line of integration than the other 5s, giving them the license to explore their erotic side as well as transform their sexuality into a major site of intellectual inquiry and exploration. A great example of this is Homura Akemi from Mahou Shoujo Madoka Magica. Her love for Madoka influenced her to chase an idea that wound up destroying and entirely upending the exploitative magical girl system.
Speaking of lines of integration, SX5s also possess many of the key traits of 7s and 8s such as raucousness, assertiveness, playfulness, novelty-seeking, eroticism, romanticism, charlatanism, and congeniality. In fact, SX5s are the most friendly, flirty, and personable among the E5 subtypes. I've personally been mistaken for an 8 (not a 4) in real life.
While the sexual instinct allows the SX5 to expand in response to the psychological constraints of avarice, the SX5 can swing to other side of the pendulum, falling into intellectual obscurity and becoming even more avaricious in an attempt to safeguard and validate their eccentric ideas, and by extension, themselves. Unlike the other E5 subtypes, who proudly assume the role of the detached observer, SX5s don't readily buy into this illusion. In fact, they are aware that self-concept and external truths are deeply intertwined, which is reminiscent of the old adage espoused by Rene Decartes, "I think; therefore, I am." There is a mutual recognition at play between ideas and identity, so the SX5s inclination to embrace such fact enables them to passionately defend not only their truths, but also the truths of the world. As such, the SX5 is more likely to reject ideas that are not fully-embodied and tethered to the real-world. This attitude can render SX5s solipsistic and delusional, but it can also make them more grounded and present in truth and reality.