It's similar in the way that it's quirky, maybe not as quirky as Kotoko though.
There's also some comedy in KonoKoi, and a much more mature cast.

The romance factor is unrequited for the most part, similar to Itazura na Kiss.
There might be more heartache in KonoKoi because it only has ten episodes, while ItaKiss has two seasons.

The age gap between both leads are at least over ten years.
Naoki (Yuki Furukawa) and Kotoko (Honoka Yahagi) are ten years apart in age, while Takumi (Tomoya Nakamura) and Kiki (Nana Mori) are fourteen years apart in age.