Basic Trope: Women are portrayed as having no sex drive.
Straight: Alice is uninterested in sex, as are the other females in the series.
Alice and her female friends are Celibate Heroines who find even the idea of kissing repulsive, and don't find lewd jokes any bit "funny".
All women on another planet are so disgusted by the thought of sex, that they have to keep reproducing the human race through asexual means to survive.
The (il)logical extreme! Every single woman hates sex so much, that all female scientists work together to invent a method of asexual birth, where the offspring has no interest in sex, all while killing off all themen.
Downplayed: Alice is not a prude, but just is not as interested in sex as Bob.
Alice has a sexual dysfunction (dryness, persistent pain, difficulty maintaining arousal, etc.) that makes it difficult, if not impossible, to enjoy sex.
The women in the series hate themselves for thinking these thoughts.
Beth only sleeps with men to feel good about herself.
Parodied: Alice goes near-catatonic with disgust if the word sex is even mentioned... much to the delight of Steve, who loves Trolling the heck out of her.
Zig Zagged: Alice doesn't enjoy sex, but Beth does. Then we find out Beth only sleeps around to feel good about herself. But Clarice genuinely enjoys it - because she's "abnormal". And yet after her Heel-Face Turn, she gets a sex scene where she has The Immodest Orgasm. Which it turns out she was faking.
Alice and most other women of the show Lie Back and Think of England and this frustrates their boyfriends who eventually leave them all because making love to someone who doesn't respond just doesn't feel as good as when someone enjoys it.
Alice is asexual, as it's a standard part of human sexuality, and is put down and insulted because of it.
Reconstructed: Beth, however, soon teaches Alice that sex can be okay. Alice, however, decides that at the moment she's personally not too interested in this whole "sex" thing anyway, and continues being a prude.
Plotted A Good Waste: Alice doesn't enjoy sex with Bob because she's secretly a lesbian, but she's afraid to tell him.