விரலைக் கொடுத்தால் மணிக்கட்டைப் பிடிப்பான்
Viralaik kodutthaal manikkattaip pidippaan
Meaning
Give some people a finger and they'll grab your wrist - describes those who take far more than what was ever offered.
Story
A shopkeeper let his business partner temporarily use one small room. Within months, the partner was running the entire shop as though it were his own. "I gave a finger," the shopkeeper later admitted, "and he took my whole wrist."
Reader's Note
Keep your boundaries clear - generosity shouldn't quietly turn into being taken advantage of.