Learn English – word or an idiom for people who only spend their families’ money and fool around

The word I use at work is just "late". They're all late.

Unfinisher doesn't exist, but non-finisher does.

Your question is a little ambiguous though. Are you looking for a word for people who do finish, but after the deadline (flaky), or for people who never complete the work at all (non-finisher)?

One way of selling your virginity is to "auction" it to the highest bidder. Compared to prostitution, auction, has a slightly more positive connotation in that the owner is in control of the transaction, and should be able to pocket the entire sum unlike many instances of prostitution, where the fee is divided between the girl and her procurer.

From the Daily Mail:

Bids reach $35,000 for virginity of high school student, 18, who is auctioning herself to pay for sick mother's medical bills.

After a 20-year-old Brazilian auctioned off her virginity three months ago for $780,000, high school student Rebecca Bernardo made the decision she would also offer her deflowering to the highest bidder. [...]

Despite taking money in exchange for sex, Miss Migilorini denied being a prostitute.

She told the New York Daily News at the time: 'If you only do it once in your life then you are not a prostitute, just like if you take one amazing photograph it does not automatically make you a photographer.'

In different cultures virginity has been and still is regarded as a valuable commodity and the right to have sexual intercourse with a virgin can be bought. For example in Japan between 1603 and 1868, a maiko, an apprentice geisha, would sell her deflowering to her patron in a ritual called mizuage. Although it officially became illegal in 1959 there have been reported cases as recent as 2001.

Wikipedia

"The money acquired for a maiko’s mizuage was a great sum and it was used to promote her debut as a geisha, but this was not considered by geisha to be an "act of prostitution."

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