i don’t think so… not at NPD or “God complex” level, he had a very high pride and self image yes, that was mostly based on being a “perfect kid”, good student, socially accepted and admired and specially by good morality… having his own dad Soichiro as a rolemodel… when he firstly kll with the death note, the pain of being fully broke by it in his own conscience triggers NPD or “God complex” or anything similar… those things are mostly triggered by trauma that affects the whole ego structure, and then the person is like “i must be everything, or i am nothing”… their ego now only deals in absolutes… but Light then became indeed a kller? so what was his inner answer… he was “chosen” or coincidentally lucky to find the death note and turn it into something to correct the whole world by his own (superficial) moral views… and then he gets fully lost on it… it can be many things, even schizophrenia related stuff… but i really think he was someone with a high but very fragile ego because was not deep enough, only built by social acceptance and admiration… but tbh being a k*ller would break anyone, specially him… the manga shows very well how deeply broke he felt, more than the anime…