The word you are looking for is "잠지". Even amongst Koreans, "잠지" is often misconceived as being vulgar, profane, but the term itself is a native Korean word that refers to the female genitalia. Some consider "잠지" a euphemised form of "보지", which (in most circumstances) is thought to be rather more offensive despite being used and found in monumental Korean literatrues. Though "잠지" originally could be translated as "penis of a little boy", more often than not it is also understood as a euphemism for the vulva.
("질" is a more anatomic term for the vagina (not the vulva, if you'd like to be more specific), and it is neither childish nor vulgar.)
According to a Korean Wiki site, the term's usage is in fast decline, but it is the closest to your description that I could find. Hope this helps. Also, check out the following link (a Q&A page from the National Institute of Korean Language), it explains how Korean culture and its tradition (which tended to hush up rather explicit or frank discussions of female sexuality - though it is changing nowadays) may have led to such absence of the terminology.
1. Where to begin, I mean, if we are talking strictly in terms of "the monumental Korean literatures that contain the word '잠지' or '보지'", I was referring to "태백산맥" and "토지", but I am sure that's not the case here. Anyway, those are very important and influential literature pieces culturally, historically and academically so they are worth checking out:
The Tae Baek Mountains - Wikipedia
Toji (novel) - Wikipedia
Bear in mind though, those two are quite challenging (even for average native Korean readers). They contain some words and expressions that still cannot be interpreted to this day. Talk about a difficult task eh?
2. The following is a short list of "must-read" Korean literatures taught nationwide in both middle and high school. Understanding of these literatures is thoroughly tested in "수능", the infamous college scholastic ability test:
눈사람 속의 검은 항아리-김소진
메밀꽃 필 무렵-이효석
고향 없는 사람들-박화성
서울, 1964년 겨울-김승욱
(Source: 한국문학 명작선(전4권) 한우리북스 명작선)
3. As for more recent, 21st century literature works and those that are relatively well-known to an international audience, there are Kim Young-ha, Han Kang, Hwang Sok-yong, Hwang Sun-mi, Kim Suki, the list goes on and on. Take it with a grain of salt as everyone has different opinion and tastes. "The Vegetarian" and "소년이 온다" by Han Kang are sensational and widely read both domestically and internationally.
If you are into works of young, up and coming writers, "젊은작가상 수상작품집" series is definitely worth checking out. It is an annual publication that compiles 7 of the most critically acclaimed, positively received works by different, up-and-coming authors (those with writing career of 10 years or less under their belts). In fact, this type of "compilations" or "anthologies" is not so hard to come across.
I am sure other members of the forum will be able to recommend other prominent literature works from different era, different genres, different movements. Stay tuned.