Where do I think Chantal learned these behaviours?
She was born of a teen mom, who had not even begun her own independent adult life. Her mother Kim continued to date and try to attract male attention, and ultimately, find a partner. While she continued her teen life, she left Chantal with her own mother. Chantal's grandma; who had been "abandoned" by her husband because he couldn't deal with her depressions. Then there was Chantal's own early relationship with her bio-dad, who from the sounds of it, was unstable and unreliable.
Having a partner was what the two most influential women in Chantal's life taught her was of the utmost importance. Along the way she learned that being "sexy" and appearing a certain way was how you attracted and kept a man. This behaviour was also modeled by her teen mom Kim, and I suspect she may have learned in even more dark ways. We do know that Chantal was the victim of at least one paedophile. (french lover) and I suspect that there were more predators who crossed that boundary. I believe Chantal was hyper-sexual from a young age, and her behaviours to act that out are part of why she was sent to a group home. (kissing posters of teen heart throbs until she wore their lips off the paper, "humping" her Alf stuffy, threats to call cops on her stalking behaviours) The expression "boy-crazy" was not an exaggeration when it came to Chantal. Also, because of the estrogen produced by her fat, Chantal may have experienced precocious puberty. I am not placing blame on Chantal as a child. Chantal can be very driven and stubborn when she sets her mind on something, and she is not easily dissuaded. A child, however, cannot be and should never thought to be a "seductress". A child cannot give consent no matter how "willing" they seem to be.
Chantal has bragged about how "good" she is at giving blowjobs and handjobs. Getting good at whatever sex acts she is able to perform is important to her. Chantal was taught that having a partner is a woman's most important accomplishment in life. She has also learned that sex is the way she can attract and bind a partner to her. Sex is the currency of the transaction. I believe that Chantal is hypersexual when she has the chance to be ( I just need to get into his house), because she thinks that is the only way she, as a morbidly obese woman can get and keep a man. And she has had success. She found a certain population of men who also regard sex as the most important use for having a partner. Her longer term relationships have all been transactional. It is all very icky, and gets dark very quickly. I believe her when she says that she would not be in the relationship with Salah if they were not having sex.
She is who she is, and while I am not unsympathetic to her past and where it went badly, the fact that she puts it all on the Internet for attention and for our collective entertainment and refuses to even begin to fix it, makes her an evergreen cow.