Love & Pop (1998) [Japanese: ラブ&ポップ] was adapted from Ryū Murakami's novel Topaz II which is about enjo kosai [援助交際] or the practice of Japanese high school students accepting payment to go on dates with men.
The first "date" took place after two teens were paid 10,000 yen to have lunch with a middle-aged businessman. Subsequently, the nymphets were approached by a man who offered them 7,000 yen to have lunch in his apartment. In an effort to raise money to buy a ring, the girls accepted 50,000 yen to go to karaoke. After singing and eating with the nymphets the man fetishly collected the girl's saliva covered muscats. And the next to last ephebophile forced one of the nymphets to give him a hand-job while they were on a "date" in a video rental store.
I briefly wrote about Stop The Bitch Campaign (2001) which is another enjo kosai film, and I have a number of other Japanese films to review, but I haven't come across any films about joshi-kosei osanpo [Japanese: ＪＫお散歩] which is where the men frequent JK cafes to "chat for half an hour" with nymphets for approximately $30.
Of course some of these dates lead to more than just lunch, karaoke and even hand-jobs.