Considering this is all Anime Genre ( and should be moved). I wouldn't pick Death Note, the trouble and the awareness that a lunatic teenager is mindlessly killing people and the whole society is in fear of everyone around them. Too contreversial.
I would probably pick a harem, the possibility of hot teenage girls surrounding me would turn me on. The reality is, I'm a kid who's a sucker for a hot chick. Imagine Love Hina in reality, I'm having a bath with weird and wonderful teenage balls of testostarone, sweet. Living in a bath house with chicks getting changed would be awesome. Although, I'd be cool enough to eliminate all the sexual tension between the guy and the girls because I am that awesome.
Thanks for reading my rant.