其实= =
这是中文式的英语。
从英语的角度来说，句子完全不完整。
也没有出处。
因为英语里压根没这个说法。
Come and never leave。
如果你是要表达Once come,never leave.的中文意思的话。
也可以说是流连忘返吧。
流连忘返
indulge in pleasures without stop ；
enjoy oneself so much as to forget to go home ；
enjoy oneself so much that one doesn't want to come back ；
linger on, forgetting to return；
on the scoop
1. The young man who is enchanted by the night scene does not want to go home.
那个年轻人被这夜景所吸引而流连忘返。
来自《现代汉英综合大词典》
2. The West Lake in Hangchow is a magnet for visitors.
杭州西湖使游客流连忘返。
来自辞典例句
3. He is a nighthawk, always hanging around in the night clubs.
他是个夜游神，常在夜总会流连忘返。
来自辞典例句
4. Only antiquarians and literary amateurs care to look at the gardens with much interest.
只有考古学家和文学爱好者还会在花园里流连忘返。
来自辞典例句
5. Ordinary Chinese are also fascinated by Singapore as a tourist spot.
民间访客流连忘返。
来自互联网