As long as they don’t do it on real humans nobody is hurt.
Living out the fantasy of having sex with children (or other harmful sexual practices and fantasies) wit AI or alike can strengthen the wish to actual do it in RL. It can weaken the strength to abstain. If you constantly have fantasies where for example "the child AI wanted it too" then it can desensitize you and making it harder and harder to push that thought aside when in a tempting situation. Instead of replacing the real thing with a fantasy you are preparing for the real thing. Some pedophiles already interpret children's behavior as sexual that isn't at all, but the AI might be told to act in that way and strengthen these beliefs.
This is still something that is and has to be studied more to fully understand it. Of course this is difficult because of the stigma. There might be differences between people who only are attracted to children and ones that are attracted to adults and children and there is just not enough data yet, but even the communities in which pedophiles who do not act on their attraction discuss coping strategies this is heavily discussed and controversial.
If you are interested in the subject a bit more, this is a start: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8419289/
My e-book reader (Tolino).
As I got older and had problems with my eyes, this was a game changer. I had basically stopped reading books and now I do it daily. I can choose the font and letter size, background color, and backlighting based on what works best for my eyes that day and the light where I am.
Being able to hold a very light device with a big screen when I would have to balance a heavy weight as a paper book is also great, and I take the reader with me everywhere, whereas a big book would stay at home most of the time.
The reader has a bigger screen than my phone and the battery lasts longer.
The reader works flawlessly with my library, so I don't have to buy books, which keeps costs down, and I don't have to leave the house to get a new book.
Calibre helps us share books in our family, which is one reason we've stayed away from Amazon's Kindle, so we've all gone to ".epub".