Well, here's my story:

I started with the game few weeks ago and everything is going pretty well, but I have a small question:

I've been talking with a Hb7 and now she is madly obsessed with me, she sends me lots of IOIs all the time, and we are going to see each other in a few days for a "massage", that i'm pretty sure it'll finish in the bed.

The problem is that in her group of friends there's an amazing hb9 that sends me lots of IOIs, but I haven't talked to her yet, so here's my question, If I fuck the HB7, will that improve or destroy my chances to fuck the HB9?

I don't know if this matters but i'm 18 and they are 17

There's no way of knowing the answer to that because there are so many variables that would affect it.

With that said, it shouldn't matter to you. If you're on the fast track to getting laid with the 7, focus on her.

It will not hurt your chances, girls (especially younger) love "bad boys". Having a reputation of hooking up with other girls, while remaining emotionally unattached, will certainly raise your DHV. As well as being around other girls, and other girls "chasing" you.

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They call me the cat whisperer, cause I know exactly what the pussy needs.

Yes, but conversely, if you fuck a girl's friend, she'll be less likely to fuck you in most cases for fear of losing that friend.

I think it'll improve your chances with the HB9. Girls at 17 are fucking immature bitches... No values. You should start talking to the HB9 but very casually. She's jealous of the HB7 and wants to suck your dick. So plow the HB7, and then the HB9.

Go get them both you bad mother fucker.

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Before she can respect you, you need to respect yourself.

Certainly in the realm of possibility, 50/50, girls are shady too, and there is the-want what they can't have- aspect.

Tag the 7, try for the 9. win/win

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They call me the cat whisperer, cause I know exactly what the pussy needs.

This actually happened to me. Almost the exact same thing. In your scenario I made out with hb7 which led to her telling her hb9 friend. Which ended up as the hb9 getting pretty mad and jealous. Anyways I worked with hb9 so after the day it happened we went out and talked about the whole thing. She was fine with everything that happened and cooled down. The next weekend I had a party. Guess what we fucked. At a young age she was 17. They love fucking but no strings attached they won't say that but really they do. I actually lost her because I got to attached. Shit happens but you learn from it. Show her who's boss. Make her really work for you.

Wow! thanks for so many answers, I think I'll go first for the 7 and then try with the 9, actually they're not like best friends, so I don't think the 9 would get mad (well, not too much).