expression
can't take one's eyes off; must keep a watchful eye on
Used when something is so captivating or important that you cannot look away, or when a situation requires constant attention.
その映画は面白くて、目が離せなかった。
The movie was so interesting I couldn't take my eyes off it.
小さい子どもがいるので、目が離せない。
I have a small child, so I have to keep a watchful eye on them.