"Virginity/chastity could be said to be a long-term asset, since men prefer a female who will not potentially cuckold him. However, your second statement is not true. Many girls would still give up their virginity even after being informed of the loss to mate value. Apart from this, and perhaps more significantly, your argument applies not only to girls under an arbitrary age of consent, but to those over it as well. Females over 18 (or whatever the AoC is in your country) also suffer a loss to mate value from giving away their virginity. In fact this argument has no age dynamic and is reminiscent of the old way in which sex was regarded; age is not relevant, but marital status."

A house is also a long term asset. And a female (or male) under 18 is not allowed to sell a house - not even if she or he actually gets a fair market price, or more. Whereas a female or male 18 or more is allowed to sell a house, even at a loss.

"Furthermore, it is not clear that a man taking a girls virginity would be fraud. Your argument rests on the notion that chastity is an asset and one that ought to be appreciated by a girl, otherwise she mustn't be informed. Except that many girls will not apply quite as much weight to this as you do. What you are doing, is insisting that a girl attribute as much weight to this fact as you do. Facts may be facts, but individuals should be free to attribute as much weight to them in their decision making process as they wish. Your argument implicitly seems to deny agency to individuals. A man taking a girls virginity on the promise of marriage and then reneging on that promise would be fraud. A man taking the virginity of a girl who is unaware of the loss to her mate value, or does not attribute as much weight to it as you think she should, is not fraud."

If a 8 year old girl moves in with her foster parents and sells a home she owns for what is a pocket money compared to market value of the house, is she a fraud victim? If she gets the market value but then uses it to buy an amusement park she does not need, is she a fraud victim?

A 18 year old girl can do the above. From which age should a girl´s assessment of the real value of long term assets she considers selling or buying be respected?

"Is it fraudulent when a car salesman sells a car to a customer that he knows is not robust, and will have alot of problems in a few years time, while the customer does not know this? Of course not; the onus is on the customer to do his/her research when buying a car."

Not but not "of course not". That the onus is left on the customer happens to be the law, but it would not be unreasonable to put it on the seller.