FAN SERVICE!!! Boys....Boys....and more BOYS! For me having an amazingly hot main character is enough Fan Service for me but when an anime has more than one hottie or cutie I cant help but love every moment! (Nose bleeding at the same time xD)
Having an amazingly good character with a good plot and voice that matches with the personality is already good but making them hot is even better!
Of course I didn't forget the guy's Fan Service! Amazing Strong Women that have looks to match is an extra bonus in anime! There are some animes that cross the line with Fan Service when it comes to the ladies but hey guys like it that's for sure xD