When guilty

 When they are guilty, they don't answer. The silence is guilt. Sometimes they deflect or attack. 

Egotistical but insecure

 

Narcissists think they are great people but engage in tactics such as blame shifting to protect their fragile egos. They are extremely insecure. That's why they can't show you their true face.

And covert narcissists are extremely insecure and jealous.

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So are they egotistical or insecure? They are both. A narcissist doesn't see himself as bad. He needs remorse for that. What you are seeing in him is narcisstic insecurity.