Well, I don't know about it being short. It's just not a porn game per se, because I like to build up the relationships first and we're just now slowly getting to the part where the MC gets close enough to the girls
My suggestion would be to just give it a try if you like character development, because that's one of the things I pay a lot of attention to in CH.
As for grind.. there is none. Neither is there edging, I'd say. Teasing, maybe, but that's not intentional and rather a byproduct of the story and how things are going between the MC and the girls.