Kae Serinuma is a fujoshi in her second year of high school, happily fantasising about shipping the various cute boys at school with each other. Kae is also, well, fat but goes into shock in episode 1 Can She Do It? A Real Life Otome Game when her favourite anime character is suddenly killed off.
A week later Kae emerges from her bedroom, having not eaten anything in the interim, and is now, well, gorgeous. The cute boys she was shipping with each other are now chasing her, and she has no idea what to do about it.
The OH DEAR
Weight loss doesn’t work like that, and there are significant body image issues at work here.
Particularly that girls are only worthwhile as people if they are conventionally attractive. To be fair, I think Igrarashi arrives at a much more mature outlook in episode 5 Back to My Original Self! What Should I Do?, but very little is done with his enlightenment after that.
It’s arguable as to whether Kiss Him, Not Me is better or worse than Anime De Training! Ex in this respect. Kiss Him, Not Me isn’t even trying to be realistic, whereas Anime De Training! Ex was selling itself as an exercise show. I’m slightly inclined to think Anime De Training Ex! is worse, but I’d like to hear your opinions.
As far as watching Kiss Him, Not Me goes, you either accept this as the fantasy premise to set up the comedy, or you don’t watch it at all. In my case I accepted it whilst I was watching it, but with a strike against. Back to My Original Self! was a second strike, and had the series gone there again I would have dropped it.
One social aspect that Kiss Him, Not Me does handle well is Kae’s identity as a fujoshi. Whilst she initially tries to hide it from the boys, she gives up on that completely by the end of the joint date in A Real Life Otome Game, and basically says “take it or leave it, this is who I am”.
Whatever else can be said for Kiss Him, Not Me, it is a consistently funny show. Kiss Him, Not Me has fun with the reverse harem set up, how Kae sees the roles of the boys from her perspective as a fujoshi, the boys trying to understand Kae, and the boys trying to prevent any of the others from getting ahead with Kae.
There’s quite a lot to work with there, and for the most part Kiss Him, Not Me does a fairly good job with the material resulting in a fair bit of fun to be had watching it.
There’s not as much fanservice as I feared from the opening and especially the ending. However it is there, particularly in episode 9 The Beach! Bathing Suits! Time to Get Serious! which is exactly what it sounds like.
To be fair, and as suggested by the OP (see below), there’s also a bit of fanservice from the male characters.
The Road to Nowhere
If you look at other harem/reverse harem shows, even parodies like Ouran High School Host Club, there’s still going to be a resolution… eventually.
Kiss Him, Not Me?
Not so much.
In fact the season finale is explicitly scripted to avoid a resolution. What Kiss Him, Not Me is doing here is protecting the core setup for the comedy, which is fine up to a point. After that point, the story needs to move along or the comedy will get stale anyway.
You can stave off that moment for a while by adding new characters as Ranma ½ did, but that will only work for so long. I would suggest that as of the end of this season Kiss Him, Not Me is really at that point now. A second season would need to get off the fence and move into an actual romance for Kae to be worth watching.
So long as you can accept the premise and that road to nowhere, Kiss Him, Not Me is a fun show worth watching once. It’s probably not worth a rewatch, and I probably wouldn’t watch a second season, but I had fun with it this season when I needed mindless diversion.
Here’s the OP:
 Literally: What’s the Point of Me Getting Popular?
 Unless it appears when I’m in the middle of a brain-draining project and I need something mindless. That’s my excuse, and I’m sticking to it.
 Although, on second thoughts, Kae may have kept her fujoshi-ness to just the core group rather than letting it out to the school as a whole.
 IIRC Haruka was a generic anime otaku rather than a fujoshi in Nogisaka Haruka no Himitsu.
 Plus Nishina, the female doujinshi author who also idolises Kae (and for somewhat better reasons I must admit).
 As far as I know a second season hasn’t been announced.