DDLG or Daddy-Dom-Little-Girl is a type of roleplaying many women love where an adult woman pretends to be a little girl and pretends her partner is her Dad. Sometimes while masturbating or having sex.
In a sense almost all adult hetero relationships are DDLG roleplaying as most women expect their partner to provide resource security for them, and most female popular depictions of romance contain infantilization of the female as a source of excitement.
DDLG in fiction
DDLG as a plot device is used in numerous fanfictions and yaois. Such content usually involves fictional characters, replacing the "woman" of such situations with a feminine male character or shota, (the uke male), with the father usually being the (seme). These usually include incest, and, "entirely fictional", pedophilia. The gender role reversal is sometimes because many women feel guilt, shame and disgust for if the young person was a woman.
Women on DDLG
Many women, especially feminists, hate this genre. But a large contingent of women enjoy DDLG and hide their interest in it, in fear of being considered a slut by society. Many women also cope by attacking similar genres such as lolicon or the mommy gf Archetype. This is similar to how many closet homosexuals will attack other homosexuals to deny their homosexuality.