Well you're not going to give me any blood either

Today I volunteered my finger to complete a quality control test on the equipment we use for testing INR levels for people on warfarin. It was giving us some variable readings and needed to be double checked. Well apparently my body didnt want to give up any blood after the finger stick and the pharmacist used the line above on me. I called her a vampire and said she shouldn't be so greedy. We had a good laugh and then milked my finger for blood.