The lady who put oil on Jesus from an Alabaster container had previously been a prostitute. She was a sinner saved by Christ and Jesus said, "Those who have been forgiven of much love much. She also wiped Jesus' feet with her hair.
The Christ is the anointed of God but anyone can further anoint someone with oil - which is what the prostitute did for Jesus that day.
The Pharisees were absolutely incensed about it, so was Judas who thought it was a waste of money because he said that money could have been given to the poor - although he was always stealing money from the purse anyway, so he probably wanted it all along, but Jesus said, "The poor you have with you always, but you won't always have Me" and He was pleased with what the woman did in anointing Him for His death. He said she would always be remembered and memorialized for her action that day