If you liked the Koi Neko manga, the Anime-Planet community thinks you'd like:
Something tells me that you would enjoy one of those series if you liked the other, but I can't quite tell why. The best I can come up with is that both series are comedies that feature an idiot couple. Despite the lack of evidence, I do encourage you to give those series a try, especially if you read one and liked it.
In both manga a cat was turned into a catgirl and now pesters some guy. In both manga the catgirl has common sense of a cat. As a whole, Koi Neko is the better one, because the jokes are funnier and there is actually some romance there. Nonetheless, if you liked one and are looking for more, the other manga might be the thing.
It's guy bothered by doggirls in one and guy bothered by catgirls in the other. In both series (at least) one of the animal girls is head over heels in love with the mentioned guy. I found Koi Neko to be much better of those two, but I guess they are kind of similar, so if you liked one, you might try your luck with the other.
P.S. Koi Neko has very little fanservice, but Inumimi isn't exactly "lacking" in that aspect, so keep that in mind.
Both manga feature a lovestruck catgirl who is very dere-dere towards her object of affection. Koi Neko is more comedic than Koneko Pancake, nonetheless if you liked one of them it is very likely that you will like the other one as well. It is important to mention that the catgirls in both series have (surprise surprise) cat-like behavior.