What do you class as a child groomer?

So apparently I sparked a little debate in YouTube comments. I watch two hot takes quite often and in this Reddit situation this girl 19 has 5month old triplets with male 23, they started dating when she was 17 and him 21. Someone commented saying how could they not mention the age gap and the fact he's a child groomer. How he probably befriended her for over a year and then started dating the second she was legal.

I simply said to say someone is a criminal without any proof or extra information is a bit over the top. All we know is she was 17 when they started dating 🤷‍♀️. I also pointed out that 4 years isn't that big of a deal as there're plenty of relationships with bigger age gaps hell the male and female celebs do it those their 60/70s are going out with 20/30 year olds.
What do you class as a child groomer?
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