Sitting up tends to trump her relaxing place, and she shifts to hop down when he scruffs her-

The purr immediately becomes a low, warning growl. Watch what you do with that hand buddy or you are going to lose it-

Oh. He's putting her down in his lap. That's fine.

The growl subsides as abruptly as it had started as she settles into his lap, though the purr doesn't start up again quite yet. She's still miffed at being moved like a disobedient kitten.