would this bother you?

so the guy ive been seeing for the last few months last night opened up to me and when we started talking about how many people we've both slept with i told him my answer which was just the one person (my ex of 2 years) he however ended up telling me the truth which i think i was a little unprepared for. He's slept with over 150 people to the point where he's actually lost count. He said he went through a bit of a man whore stage and that he's not about that life anymore but i kind of dont know how to feel about it.. thoughts?