The Sentinels without poisoning the soil

The claimed object's reaction was quite unpredictable - as Deirdre cooed, Sarah's eyes grew wide and she retreated, staring now at the girl's mouth. When she was sure that there was no other sound coming out, she leaned forward and sniffed the dark lips, her nose touching them lightly. She then decided to poke them a bit with one paw to see, if they would make more sounds.