Jailbait sites legal?

You are wise not to visit the subject website ever again. Without reviewing the website (which is not advised) it is unknown whether the website is properly legal., from where it generates, or what compliance it follows.

Illegality is generally not related to morality. This is a crucial distinction. Therefore, in order to figure out if something is illegal, we look not to morality but to the law as it is written. For example, going by your example, we can look at a relevant federal statute, 18 USC § 2256(8), which defines child pornography as: [A]ny visual depiction, including any photograph, film, video, picture, or computer or computer-generated image or picture, whether made or produced by electronic, mechanical, or other means, of sexually explicit conduct, where— (A) the production of such visual depiction involves the use of a minor engaging in sexually explicit conduct; (B) such visual depiction is a digital image, computer image, or computer-generated image that is, or is indistinguishable from, that of a minor engaging in sexually explicit conduct; or (C) such visual depiction has been created, adapted, or modified to appear that an identifiable minor is engaging in sexually explicit conduct. We then have to figure out what is "sexually explicit conduct" -- is it a minor, dressed in underwear, with a sultry look? 18 USC § 2256(2) defines "[S]exually explicit conduct" as (A) Except as provided in subparagraph (B), “sexually explicit conduct” means actual or simulated— (i) sexual intercourse, including genital-genital, oral-genital, anal-genital, or oral-anal, whether between persons of the same or opposite sex; (ii) bestiality; (iii) masturbation; (iv) sadistic or masochistic abuse; or (v) lascivious exhibition of the genitals or pubic area of any person; (B) For purposes of subsection 8(B) [1] of this section, “sexually explicit conduct” means— (i) graphic sexual intercourse, including genital-genital, oral-genital, anal-genital, or oral-anal, whether between persons of the same or opposite sex, or lascivious simulated sexual intercourse where the genitals, breast, or pubic area of any person is exhibited; (ii) graphic or lascivious simulated; (I) bestiality; (II) masturbation; or (III) sadistic or masochistic abuse; or (iii) graphic or simulated lascivious exhibition of the genitals or pubic area of any person; The closest we can fit these images would be "lascivious exhibition of the genitals or pubic area", but because the minors are clothed, this prohibition would not fit very well. Even if the website promotes its images towards satisfying the sexual desires of its users, the way the law is written is not aimed at how the users end up using the images, but is simply a prohibition on what the image can contain. People can have all sorts of things that they find sexually attractive, and so trying to ban based on sexual preferences (e.g. any photo a pedophile finds attractive may well be any photo of a child, clothed or otherwise) would be an unworkable standard. You may also ask why would such images not be banned? An educated guess would be that it would be very hard to police because it is much harder to figure out what is "not OK" when a minor is clothed and not doing anything explicitly sexual. Otherwise, the law might prohibit someone taking an innocent picture of their child in a bathing suit, or in their pajamas, or even in a ballerina costume. Hope this helps!