Many stories focus on sex and romance. Those are overwhelmingly the kinds of intimacy featured in fiction. Even outside the immediate sphere of erotic and romantic stories, they comprise major subplots in most genres and many stories. Attention to other types, expressions, and experiences of intimacy is rare. This largely ignores nonsexual family relationships such as siblings or parent/child. It shortchanges close professional relationships such as a cop's beat partner or a soldier's buddy. It tends to leave asexual people off the map altogether. Even for readers who like stories about sex and romance, this can get old -- especially if the writer doesn't pay any attention to the development of intimacy but just shoves the characters into bed as fast as possible.
Nonsexual forms of intimacy can add a great deal of depth and variety to fiction. On one end of the spectrum, they provide extra steps to support the journey from meeting a potential mate through romance, sex, and marriage. In the middle, they convey the import of family and professional connections, distinguishing those from more casual acquaintances. On the other end, they form much of the glue in primary relationships for people who don't base their ties on sexuality. Sex and romance are valuable, but they're not everything. Nonsexual intimacies are the "show don't tell" conveyance for the rest of the serious relationship field. Here are some examples and their story influence.