This is akin to Love Bombing and often used by cultists with fresh recruits - who tend to be lonely and isolated, those most vulnerable to this technique.
Another variation is: "I think I'm falling in love with you."
Yes indeed, you are. Madly, crazily in love with me. Gaspingly, frantically, lustfully in love with me. To the borderline of utter silliness.
Saying it to an MGTOW is amusing, at the least. It certainly puts the more experienced male on his guard - whether MGTOW or PUA or otherwise.
It's just another cynical and selfish manipulation by a woman to entrap a man into giving her what she wants.
Which is why some PUAs will use it in return on women. It's simply another weapon in the arsenal to encourage her to part her legs for you.
Women use it on Men, Men use it on Women. Thus the cycle of cynicism and manipulation goes round and round, escalating each time, a vicious exploitation that violates the social construct of mutual civility.
Implosion will occur eventually.