My older two get to each pick a short book -or- a chapter from a 'big' book ( we have read
Farmer Boy from the "Little House" series; right now it is one of the 'Captain Underpants'...

) It is a privelge which can be taken away if they don't mind.
Yes - he is prob. wanting you to stay and read to push back bedtime and get your undivided attention. Set your goal/limit and then say "Good-night"