We calls it being a "sneaky gorilla". He's referring to the book Goodnight, Gorilla where a precocious gorilla sneaks out of the zoo and follows the zookeeper home and creeps into his bed.
Even if Sun Kissed Boys #1 is still awake, he enjoys having his sly little brother sound asleep while he reads.
How could he not love this little hand resting on his arm?
Goodnight, sweet gorilla.