Fantasy Life is a little game that I have spent far too much time on, considering it tis but a simple 3DS game. Its actually the thing that drove me to buy a 3DS alongside Pokémon, and since getting it I've spent a little over 200 hours playing it, and I still haven't 100% it. Though I have god-ranked all lives. Over all this game is addictive, the art is cute, and the story is super sweet, I highly recommend this to anyone who owns a 3DS. If you don't, I know there's a mobile game, but I believe that it's quite different from fantasy life as I believe it is a gacha game (not fully sure on that part). However, Fantasy Life I: The Girl Who Steals Time recently came out, and I've heard that's much more inline with the spirit of the original game. I think you can get it on steam, which I will be doing eventually...if I have free time..
Well, I like a fair amount of vocaloid songs, but in terms of design, I gravitate towards Miku. She's just so iconic.