Oh ok, I can't believe it I was expecting so much from her bragging about her college days mentioning her friend Hannah teaching her to do a deepthroat just to be reduced to Dylan's cock

PS still can't fix this huge inconsistency on her personality because it doesnt fit her at all hell even Camilla is ok with Dylan shenanigans without being jealous imagine...
Kelly doesn't have an easy life. Over the course of more than ten chapters, she is repeatedly shocked by what she witnesses.
She is shocked when she discovers her boyfriend cheating on her in her own home (AN08).
She is shocked again when she finds out her sister has taken her son to a nudist camp (AN08).
Kelly is shocked when she catches Brandi and Dylan naked in the bedroom (AN14).
And it comes as a massive shock when she walks in on her nephew sodomizing her sister (AN15).
She is shocked when Dylan catches her making love to Camilla and Courtney (AN17).
The final shock comes when she discovers that Emily wants Dylan to get her pregnant (AN23).
Initially, Kelly is there to protect her family from all the vices present on the island.
Yet, at the same time, she reveals an increasingly libertine side.
For starters, she isn't bothered when her older sister confesses to sleeping with a young man who could be her son's age (AN07).
Kelly isn't particularly shocked to witness an orgy in the forest, even one involving father-daughter and mother-son pairings (AN16).
She reminisces about her lesbian experiences in college with Camilla and Courtney (AN17).
She is even willing to share those lesbian experiences with Brandi, aided by Ayanna's aphrodisiac oil (AN18).
She watches Brandi and Dylan making love on the terrace without saying a word (AN19).
She masturbates in bed while thinking about her nephew, and does so again after leaving the bathroom (AN20).
She discovers that her nephew is incredibly skilled at performing cunnilingus—so much so that she decides to enter a blowjob contest, putting to use the deepthroating techniques she learned in college (AN21-AN22).
After sleeping with her nephew, she admits that Dylan is a great lover and that she is ready to sleep with him again—especially if it keeps him away from Emily (AN24).
So no, I don't see Kelly as a boring character. Initially, she wanted to protect her family, but she has now firmly established herself as one of Dylan's mistresses.
Now, what we can expect—just as Dylan did with her mother—is for he to give her the freedom to sleep with any man she desires: Tom, Harry, Pete, The Master, Diego, Shigeo, André, or perhaps Darnell, Martin, Carl, or Lukas (if they survived the shipwreck)—though almost certainly not Rory.