Error likes to take naps, no matter what time of day, three am? Nap time. Five in the evening? Nap time. Ten pm at night? Nap time that'll most likely turn into sleep time.
Error gets sleepy quickly. The reason behind this is because of the immense power he holds, his body constantly needs rest to contain the magic. If he didn't sleep much, his magic would go haywire and be sent out across the multiverse, doing his job quicker than lightning, but destroying everything, not like his goal, which is for only the original to exist. Luckily for him, he has a second option to sleeping. The strings that lay endlessly around the Anti-void, most of which being attached to the non-existent ceiling, can be an outlet for extra magic, this is why he uses them so much, and he seems to find good use for them (making clothing, puppets, and using the strings as a weapon in battle).
-Bean