We really don't know how Boo perceives himself, since he only speaks one time during the entire novel, and Scout's narrative offers few insights. Jem decides at one point, after becoming discouraged at the jury verdict and feeling that Maycomb's citizens do not support Atticus, that Boo
"... stayed shut up in the house all this time... it's because he wants to stay inside."
We do know that Boo comes out at night--he saves the children on Halloween from the attack by Bob Ewell--but whether it is his decision to stay inside the Radley House during the daylight hours or whether he is forced to do so by his brother, Nathan, is unknown.
Boo is the most gossiped-about man in Maycomb, thanks in part to the many stories spread by Miss Stephanie Crawford. Boo is blamed for
Any small stealthy crimes committed in Maycomb...
He is believed to be a killer of small animals, many of which he consumes. Children and Negroes are particularly frightened of the superstitions surrounding Boo, and they usually avoid passing near the Radley House. Jem and Scout share these views until they come to understand that the gifts left for them in the secret knothole of the Radley Oak come from Boo; they are gifts of kindness given by their friendly but unseen neighbor.