Highschool girl is obsessed with dicks and likes to mess around with a guy, her victim. However, she's not excited by the sexual act in itself but only by the member. Sexual themes are obviously present.
Both are ecchi comedies whose main female protagonist has some type of sexual obsession. Yumeko (from AGY) wants to see what male genitalia looks like and draw it, and Yamada (BGHK) is a perverted virgin who wants her first time to be with an inexperienced guy.