there is Painless tattoo , that the tattoo artist will put either cream or lotion on the tattoo area, about half an hour before they do your tattoo. Some tattoo shop will charge extra $ for that. you can ask the place i did my tattoo.
Kaz Tattoo 旺角西洋菜街百寶利商業中心18樓1802室 (旺角銀城廣埸對面) Tel : 91606336