Hello! Love the topic!
I have only done it once or twice to my boyf as he's quite shy about me doing it to him.. but fine when it's the other way round! I started at the bally and slowly licked down, to amek him feel more comfortable.. but I'd generally say go circular around the rim itself, not too wet just gentle ... I'd say to exeperiement on eachother see what you like & try it back to him?
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