Are you even reading AK? I just gave one example. Bitch-sensei kissing school boy, school girls in swimsuits, Koro being weak to porn magazines. That's definitely not one time, but actually pretty formulaic.
About HxH: Zazan wasn't fan service? Baise's 180-Minute Love Slave?
Cluck's costume? Geru's overly large cleavage? Please... that's so not "no fan service".
About Toriko: Rin isn't actually wearing high-necked clothes, is she? Love's appearance after using Sei Pheromones? Yeah, only "one time".