It's explained briefly in the translation of Ep 1, but this will all make a lot more sense if you realize that in Japanese licked (nameru) = mocked = to have a bad experience
舐める [なめる] (v1,vt) (1) (uk) to lick, (2) to taste, (3) to experience (esp. a hardship), (4) to make fun of, to make light
So basically the entire series is just a giant pun. When it ends with '... and she was licked a lot' it's the same as '... and she was mocked a lot' and you have to know which it is from context. Like whenever the class president is involved on the last page there's gonna be lickin'.