A light sleeper will always be close to it (7,4)

'a light sleeper will always be close to it' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'light sleeper will always be close to it' is the wordplay.
I cannot really see how this works, but
'light' could be 'lamp' (lamp is a kind of light) and 'lamp' is present in the answer.
'be' is found in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is located in the answer.
This explanation may well be incorrect...

Can you help me to learn more?