There's definitely a story line, you just have to watch the episodes from the first one and follow on...
That's not really a storyline, that's only continuity
Little bits and pieces they add to episodes to make them more interesting come back to haunt the writers a couple of episodes later, and seem like a deeper storyline. And before you know it, you're trapped in the web of hints and clues and odds and ends that don't let you write anything that could contradict what you wrote earlier, no matter how lightly you took it at first. In the end, the only thing you can do is just follow the story you accidentally created by trying to add flavour to the show. And if the story gets stuck, just say the last several episodes were a dream
Anyways, humouristic series try to avoid continuity like the plague, because it leads to drama, and humour is "out of place" more and more often, until you have a soap opera on your hands.
Just ask Kristopher Straub. He tried to fight it, but it's impossible.
And after you remove the 5% of each episode spent on "storyline" (as you would call it), or "continuity" (as I call it), the remaining 95% are
always... the same...