I'm not mocking you, just having some fun. It's good to relax and have a sense of humor about these things. Jokes aside though, guys who have slept with 300+ women typically have some sort of celebrity status or established wealth because guys who work for a living, were late bloomers, have some kind of budget, etc. usually don't have the time or logistical ability to game that many women while balancing all of their other activities and responsibilities as well. Even skilled gamers usually don't hit the 300 mark unless they save money and take off a year or two to live wild in some place where getting women is far easier than wherever they came from because many, if not most, guys will find that the novelty begins to fade with each new notch after a certain notch count and they will slow down, enter one or more LTRs (Long Term Relationships), and/or get married before hitting the 300 mark.
Most gamers in my observation either enjoy a steady stream of a single-digit number of females per month (thus, maybe a few dozen per year) or have long dry spells punctuated by intense periods of utter debauchery. There are others who follow a different pattern and some who make gaming women the primary focus of their lives, permanently forsaking marriage and children (usually causing them to get more notches), but that is generally what I've observed. Personally, if a guy told me that he had banged more than even 200 different women, my first instinct would be to think that he probably has made women the focus of his life, has spent a large stretch of time in Thailand or some similar place, and/or is a trust fund baby who has all day to game women. None of these things are necessarily bad or anything, they are probably just not a description of your situation.
As for your question of how to not lead a girl on, don't worry too much about this. Just don't explicitly state that you are looking for something long term. Don't bring up the issue at all and, if she brings it up, either be blunt and say you are not or be ambiguous. Females are generally more intuitive than guys and will pick up on things like that. Besides, if she is not in a committed relationship with you, and even if she is, don't assume you are the only guy she is in communication with. Females never conduct themselves without backups and orbiters waiting in the wings (often these are her male "friends" and any other non-family male names in her contact lists). This is why, whenever a female initiates a breakup with a guy, she is back in the game immediately because she already had at least one or two other guys lined up. Females never leave themselves completely open and optionless the way most males do.
Females are also not as fragile as you are implying, especially if they are not virgins. They generally will not be upset over you for long if they are for any length of time at all. Given your question, I suspect that it is entirely likely that you will be more emotionally distraught over her in the long run than she will be over you.
If you are dealing with a female, especially in a Western country (I see a Dutch flag next to your name), operate on the assumption that you are just the guy she is seeing right now and not the only one she is seeing this week/month. "She is not yours, it is just your turn" as they say. Unless you have made an explicit verbal agreement to be committed and exclusively faithful to a female in exchange for her doing the same for you, no such agreement exists and it is best to assume that it has not crossed her mind and to not bring it up. You are not responsible for a woman's emotions unless you have made some kind of agreement to be, which would be crazy given how fickle and beyond your control they are. What sort of masochist would make himself responsible for something entirely outside of his control? Don't put that on yourself, man.
Welcome to the forum and I hope you find what you are looking for here.
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