Sanko no rei (三顧の礼): the courtesy of three visits. A person of higher rank goes to a person of lower rank again and again, shows every courtesy and asks for something. The phrase comes from the Records of the Three Kingdoms. Liu Bei visited Zhuge Liang three times to bring him into his service.
A Japanese example sentence: Kanojo wa, shachō ga sanko no rei de tōsha ni mukaeireta jinzai da . She is someone our president brought into the company with the courtesy of three visits.