keep sb at arm's length
不即不离 keep sb at arm's length; be neither too familiar nor too distant 呼之即来 always at sb's beck and call 呼之即来,挥之即去 always at sb's beck and...
keep sb
... 不即不离 = be neither too familiar nor too distant 不即不离 = keep sb 不单 = not merely ...
Academic Forum
不即不离,汉语成语,拼音是bù jí bù lí,意思是指对别人的关系或态度有距离,既不太亲近,又不太疏远。出自唐·罽宾《圆觉经》卷上。