Should I stay with my bf or leave

So my bf has told me he has girls as friends and I never worried until I found out he has slept with them in the past and he calls them beautiful plus he dated a 14 yr old in his 20s he claims it was consensual and they lived together until she cheated I wish he told me all of this from the start I feel concerned he will look at his step daughter's in the same way as they turn 14 I did talk to the 14 yr old girl who's older now and she said she was very mature and developed for her age and saw nothing wrong with it