1) Egoist 2) Egotist 3) Emperor Nero, by all accounts 4) Hard person to work with 5) Hardly an altruist 6) More than a swellhead 7) Number one fan 8) One who says irate 9) Self absorbed crazy 10) Self-admiring sort 11) Swellhead 
[n] - an abnormally egotistical person
egomania, egomaniac 1. A morbid egotism; an extreme self-centeredness or self-appreciation. 2. An abnormal interest in one’s self; extreme egotism.egomaniac 1. An abnormally egotistically self-centered person. 2. A person who considers himself/herself to be extremely important and able to do anything that she/he wants to do.
noun an abnormally egotistical person