These stories have adult sexual themes . The story theme codes are described in detail here, and an alphabetical index here. There doesn't appear to be a theme code for "reluctant exhibitionism" or "self-humiliation", which are the real themes of these stories. In fact, if I had to summarize the theme in a single phrase, I would call it "self-humiliation through reluctant exhibitionism". Here, in more detail, are the themes you will find in these stories:
Exhib (exhibitionism) is one of Crysta's foibles (or is it a virtue?) She goes out naked or underdressed in public, seeking the danger and excitement of being discovered, but sometimes she goes too far, and gets caught and punished, leading to
humil (humiliation) by forcing (or tricking) the girls -- especially Donna, who emulates her mentor, Crysta -- to strip or to have orgasms (or give them to others, mostly girls) in public.
voy (voyeurism) is the flip-side of exhibitionism, at least the way Crysta practices it. Her style of exhibitionism is subtle: she prefers to be discovered "accidentally" to be underdressed, letting hapless witnesses feel a sense of shame for having peeked under her dress even as she feels humiliated by having her privates seen in this way.
Crysta seeks this form of exhibitionism / humiliation for the sexual charge it gives her whenever she's "discovered". But her behavior has even subtler side: instead of setting out underdressed, she somehow gets caught up in situations that force her to reveal her (or her good friend Donna's) goodies to public view in a way lets her appear completely innocent. But innocent she is not -- she knows exactly what she's doing, and how far she's willing to go, and then ends up going just a little further in pursuit of her own humiliation.
Donna, meanwhile, admires just about everything about Crysta, and wishes she could be "free" like Crysta. To some extent, Crysta brings Donna along as her protégée, and to a greater extent, Crysta uses Donna, forcing her into humiliating situations (such as partial or full public nudity) for Crysta's own entertainment. There's only one thing more beautiful to Crysta than Donna naked, and that's Donna naked, sexually excited, and humiliated by her nakedness and even more humiliated by her own obvious excitement! In this way, Crysta awakens a powerful latent sexual energy in Donna, who reaches heights of excitement she never thought possible.
F-solo (sex for one woman) happens from time to time as a consequence of the girls' other activities. Sometimes it just can't be helped. The world stops turning for a minute (or was it just a second? or an hour?) when the humiliation or the exhibitionism gets too intense. Although Crysta and Donna are embarrassed when this happens, it just wouldn't be right to gloss over such events. To be fair to the reader, they are described as completely as possible. Sorry, girls.
FF (lesbian sex between adults) is also a theme here, but it doesn't tell the whole story, by a long shot. The girls bring each other to orgasm in public more often than in private, and often under some sort of duress or threat of humiliation.
Coll (college) is where this story takes place. The girls are roommates in their dorm.
Anal is a theme in at more than one story -- e.g. one of the girls feels sorry that she is being forced to publicly humiliate the other by stripping her, so she makes it up to her friend (and delays the inevitable stripping) by licking her asshole, bringing her to orgasm, which, alas, only increased her humiliation, the orgasm being so public.
bd (bondage) happens when the girls are tied up and stripped as a punishment for violating some rule, such as their college's dress code, which, I must say is rather unusual: it outlaws the wearing of panties if they might be seen, such as under short dresses, and it strictly prohibits "panty lines".
spank happens from time to time when being forced to strip in public just isn't a sufficiently humiliating punishment. Some transgressions require the evil-doer to bare her beautiful ass, and prepare for a public spanking. She should be made to bend over, and spread her legs apart so her audience can see not just her asshole but her pussy as well. Then she should be forced to wait, or better yet ask, for her spanking.
ws (water sports, i.e. pissing), scat (involving feces) and caution are the unfortunate themes in just one story, in which a girl (one of Crysta's and Donna's classmates) is given a horrible punishment, the details of which I won't discuss here. The author really hates to write these scenes, but they're part of the girls' story, so it just wouldn't be right to ignore them. Perhaps you should just skip this story if you get grossed out by such shit.