It can be fun to cultivate restraint -like you are just above it all. So always play down your abilities.

"Yeah I run a bit" "I lift a little" "I am Ok at (a subject you always got straight A's in)" It takes time but eventually there is a sort of delayed gratification thing in it for you. They all talk themselves up and you praise them up while they do it, then only when they ask, you casually mention how fast you can run three miles, what you can dead lift and the fact you got first class honours in your degree.

Just be gentle with them at the end when you drop the bombshell because if you do it in a dismissive way, it can actually make them all defensive and looking for a way to beat you next time. You just want them thinking "sheesh, he's a dark horse"

Some good stuff in the comments already.

I would say self analysis is key. Take time to sit down with yourself and think about your motivations and your flaws.

"The unexamined life is not worth living"

That was Socrates who said that. He was right. Most people just cruise through life, crashing into things, never addressing their own character flaws, never even noticing them.

The fact that you realise that there is something a bit off about being proud of your body count tells me that you are on to something. Self analysis means simply sitting down with yourself and asking yourself questions, without being harsh on yourself.

Why am I proud of having slept with over 100 women? Is it some sort of achievement? Does it mean anything to me, to others?
Does it prove anything? What did I gain by sleeping with 100 women? What did it cost me? If I could speak to my young self, would I recommend this as a course of action? Am I using notch count as a proxy for something else? What might that be? Did it bring me happiness? Or peace? Or wisdom? Would I do it again if I had my time again? Why do I care if some random dudes 'accuse' me of only having slept with 2 women? Why do I care what other people think of me, other people for whom I have zero respect?

Do you see what I mean? These are all open questions, not judgemental. There is no scolding. No shaming.

It's not bragging if they bring it up. You can just casually say "yeah I do alright" when obviously you fucking slay it.

Or you can just redirect the question to a random observation. End of the day, if you are happy with who you are when you wake up and look in the mirror, who gives a fuck what they think dude?

Don't allow weaker people to get into your head. Have your own value system & principles.

It's ok to brag a bit, if your only bragging point (point of origin) is about your sex life then maybe it is because you're lacking somewhere else in your life,you don't feel as proud and dignified by your other accomplishments, it just doesn't fill you as much as women's validation. And/Or also you low-key look down on other men who don't have a high notch count, you may be competitive about it.

Try and shift your focus towards your fitness,job,profession or other skills. It is very easy to have an inflated ego after having a successful sex life,it's the easiest way I think.

By being humble.

Likely a result of some sort of insecurity from your upbringing. Used to be a problem for me too, even until recently. If you spent any amount of time feeling insignificant or like a loser, its not easy to stop yourself from rubbing it in everyones face when you level up. I know how it feels to want everyone to know what a superstar you are.

There are a number of things you'll have to address, but a big thing here is self-control. This is something you practice and get better at with time. I came to realise you start your day with a very limited amount of energy. If you don't control the things you give a fuck about, you will waste it on bullshit like defending yourself against faggots online or bragging to people who don't actually give a fuck. Instead, manage your energy, put it into things you care about like improving yourself. The more you exercise your self-control muscle the stronger it will get, and the less urges you will feel to prove yourself to people.

Its not the be all end all but its a start. Hope this helps.

What do you value more, the knowledge, work and charm it took to become the man whom 100 women wanted to fuck, or the approval of random internet strangers?

Only thing you can do is use your willpower to focus on things you actually want and the actions that lead to those outcomes and somehow learn to accept everything else is out your control.