Pure Trance

A 1998 Shojo Horror manga written by Mizuno Junko. In this dreamy science fiction fantasy, Junko Mizuno illustrates a story full of catfights, alien safari adventures, evil experiments, and a girl who dreams of becoming a pop idol signer. Following the Third World War, humankind left the toxic surface of the Earth and built an underground city to survive. A serious social problem has emerged in this new society: hyperorexia, or severe overeating, a side effect of the "Pure Trance" life-sustaining pill. The story begins in the hospital which has been ruined by a tyrannical director, Keiko Yamazaki...

Tropes in this manga include:

 * The Ace: Yuriko.
 * Action Girl: Yuriko, Masako, Yuka and.
 * The Archer: Yuriko and Yuka.
 * Artificial Human: The two assassins.
 * Alien Animals
 * Animal Testing
 * Amazing Technicolor Wildlife: According to the notes in the manga these creatures have some strange colors.
 * Ax Crazy: The Director, on so many levels. Her thoughts on childcare? Turning a pair of twins into earrings, turning a really pretty girlchild into a stuffed doll and turning the last child into a cyborg maid.
 * Badass: See Action Girl.
 * Badass Bookworm: Masako, Kajiwara and Momoyama.
 * Bad Boss: Keiko mistreats literally everyone around her.
 * Big Eater: Apparently the whole population of the world by this world.
 * Best Served Cold
 * Beware the Nice Ones: Nurse Masako.
 * Bloody Hilarious: YMMV.
 * Blood Magic
 * Broken Ace: Keiko really is a skilled doctor.
 * The Brute: Kimiko. She's also Keiko's Dragon.
 * Chainsaw Good: The Director, to absolutely nobody's surprise.
 * Child Hater: See Dark Action Girl.
 * Cold Blooded Torture: That eventually ends the life of Nurse Kaori.
 * Crap Saccharine World: The artwork is extremely adorable but the storyline proves the world pretty much sucks.
 * Creepy Twins: The twin nurses Takeko and Umeko but Keiko the hospital director from hell created them so that's no big surprise. Also Yuki and Miki, but they're the good kind of creepy.
 * Cute Monster Girl, Half Human Hybrid: Yuka.
 * Cute Witch: Yuki and Miki.
 * The Cutie: Rika.
 * Dark Action Girl: Keiko, Kimiko and the twin nurses.
 * Death By Childbirth:
 * Dirty Old Man: The Mayor.
 * Does Not Like Shoes: The whole gang on the surface world.
 * The Dog Bites Back
 * Dream Sequence: The Director has plenty of these, and they're pretty freaky.
 * Dreaming of Things to Come: And the future doesn't look pretty.
 * The Dutiful Son: Sugiura may be a dumbass that the Director has completely kowed but he still sends money to the country for his family.
 * Earn Your Happy Ending: For the nurses, Kimiko and the surface girls.
 * Everything Trying to Kill You: When escape to the surface, no one expects to see them ever again. Nonetheless, Keiko sends assassins anyway.
 * Fan Service
 * Food Pills: Since the food production is low, food pills are created as a substitute.
 * Food Porn: When real food is found again, everyone thinks it looks delicious.
 * Furry Fandom: The governor has this.
 * Gender Equals Breed
 * Generation Xerox:
 * Girlish Pigtails
 * Mega Twintails
 * Girls Love Stuffed Animals
 * Grand Theft Me: Subverted since the twins are happily cohabitating in Yuriko-chan's body.
 * Grotesque Cute
 * Hair of Gold: Professor Kajiwara. Makes sense, she's half American.
 * Heroic Sacrifice:
 * Hot Amazon: Yuriko.
 * Hot Mom: Kaori as the 4 girls' surrogate mother.
 * Hot Scientist: Kajiwara and Momoyama.
 * Humiliation Conga: The Director gets a particularly epic one.
 * Idol Singer: Seiko. Kimiko is a BIG fan.
 * Improbably Female Cast: Neither of the recurring males matter in the grand scheme of things.
 * Interspecies Romance: Rika and a Brain person, which spawns Yuka.
 * Karmic Death:
 * Kick the Dog: Over the course of the manga, the Director personally kills 3 women, abuses her staff, patients and position and eats animals from the local zoo.
 * Laser Guided Amnesia:
 * Laser Guided Karma: Keiko gets hit HARD with this.
 * Les Yay: Lots of it, everywhere.
 * Machiavelli Was Wrong: Remember kids, abuse does not improve employee morale!
 * Mad Doctor: Keiko.
 * Mad Scientist: Keiko, when she's in the mood or high off her gourd. And she usually is.
 * Magic Plastic Surgery
 * The Magic Touch
 * Meganekko: Masako.
 * Mushroom Samba
 * Nice Hat: The odango hairstyle that Kajiwara wears all the time is actually a HAT.
 * Nipple and Dimed
 * Older Than They Look: NO ONE knows how old the Director actually is and she gets plastic surgery regularly.
 * Pointy Haired Boss: The Mayor to Kajiwara.
 * Psycho Lesbian: The Director.
 * Raised By Natives
 * Rapid Aging: Yuka ages to an adult within four years.
 * Rapunzel Hair
 * Revenge: Yuriko has happy dreams of
 * Ridiculously Cute Critter
 * Robot Buddy: Nursing Robots Kiyomi and Azami.
 * Robot Maid: B-ko.
 * Sacrificial Lion: Kaori, Aiko and Rika.
 * Shojo
 * Specs of Awesome: Masako.
 * Stupid Evil: The Director. Justified by her being literally crazy and often high.
 * Supreme Chef: B-ko. She eventually writes a cookbook for all of the recipes she developed on the surface world.
 * Team Mom: Nurse Kaori and Aiko. Also the manager of the Yasuragi bar, appropriately nicknamed "Mama."
 * Time Skip
 * Took a Level In Badass:
 * Virtually everyone once they get away from the Director.
 * Tragic Dream
 * Unwitting Instigator of Doom:
 * The Voiceless: Rika and Yuka.
 * Walking Shirtless Scene: On several occasions, the Director, strippers and the surface girls.
 * What Do You Mean It Wasn't Made On Drugs: The whole premise of this story is about hyperexia induced by drugs that replace food.
 * White Magic: Usually employed by Yuki and Miki.
 * You Go Girl: Kajiwara.
 * You Killed Our Surrogate Mother: Yuriko does not take Kaori's death sitting down.
 * You Killed Our Surrogate Mother: Yuriko does not take Kaori's death sitting down.