So let's say you met her one day back and now you are going to a party with her. Isolation was not possible the whole day and both of you had some kino a day back.

In the party you see her getting close to another guy? You get a feeling if you don't intervene she will be gone.

What to do in such situations? You may intervene and ask her to come with you but will turn out needy or you can just make your presence visible and wait for her to be pulled or not pulled off by the other guy. You maintain your dignity and if she returns she is yours 100% and you can proceed with serious kino.

UPDATE

Full context since I think I missed a lot of info which is essential to the context:

Day 1 : Met a 10 during morning hostel activity .Great vibe with her. In evening got full kino with her in a pub crawl, but fumbled her as I asked her to come to terrace of hostel but she stayed at the ground with her friend. Realised the mistake that I should have stayed at the ground only to close the set.

All this while I was doing two timing with a 4 throughout the pub crawl. Some kino with her while 10 was not watching. Everyone in hostel saw it and maybe it was the reason the 10 left early.

Day 2: 10 was nowhere to see so day 2 I focused on 4. But now the 4 wanted a threesome with a 45 yr old guy. As yesterday when me and 10 both left, the 4 was in pub crawl alone and bored. I was on day 2 not able to read her intentions of a 3some and only on day 3 when the hangover was gone, I realised what happened.

So the 4 beckoned me to stick with her and her 45 year old "friend". I did not want a threesome involving a 18 yr old girl and one guy 30 yr old and another 45. Genz+millennial+boomer.

So while the 4 was deliberately getting close to the 45yr old guy I asked her to go out with me. She still beckoned me to join her friend. At this moment I got a bit angry and lightly touched her shoulder saying, if we go out, we go out now. I felt a slight jerk in her body and realised that the game is over. She went to the 45 yr old guy straightaway and I went ahead searching for the next target.

I always wonder could it have been better if I would have just hung around her like a puppy, just what the 45yr old guy did. At the end he got the bone, so being a puppy isn't not that bad ???