If you have a more open mind then id say this is a pretty average show so far.
The art is somewhat stylised and has a washed-out look as though they want it to look like a comic. Can't say i'm a fan but it doesn't particularly bother me. What can be jarring is the sound, some of the voices really give you the impression of listening to someone talking in a recording booth - there's a bottled, confined harmonic to it. Catchy OP though.
Now the central dynamic here is an older guy (27) chasing a younger girl (16/17), which seems to be a massive problem for some people, so let's see what is really going on:
Ryo is a ladies man, he has had lots of success with women since he was in school due to his looks and intelligence, and now he is quite successful at work with a nice car and his own flat. But he has a poor reputation - as he always found success easy he has never been really invested in a relationship, never apparently been 'in love' and has a history of treating his conquests poorly. In fact Koikimo opens with him walking out on his latest conquest while unable to remember her name.
So Ryo is a bit of a jerk and for my money the central theme of Koikimo is that he will have to change if he is to find love. Ichika rejects him outright in ep 1, calling him 'creepy' - and quite rightly. So do we see development from Ryo?
The answer is 'some'. I am 9 episodes in now and Ryo has acknowledged that he makes a mess of things and is not very good at relationships; frankly he is possibly even more naive than Ichika, given that he has never been in a long-term relationship before and she is far more conscious of and concerned about the consequences of a relationship than he is.
His relationship with his sister, Rio has also developed as a result of him spending more time at their parents' house (which it seems is about to be disrupted as their parents are going to be spending more time at home as per the last episode). Rio is a character I have not figured out yet - she is supportive of her brother but a real busybody, which makes it hard to like her.
The developing relationship with Rio and Ichika has a noticeable effect on Ryo at work - enough that we get a side plot about how his demeanor changes for the better, he becomes more approachable and his newfound interest in Light Novels (Ichika's hobby) brings him closer to a colleague (who asks him out).
Now for the controversial stuff:
Power Imbalance - how does Ryo have power in this situation? He is not in any sense her superior (at work or school), he doesn't really flaunt his money (he only buys Ichika flowers and plushies and gets her a Light Novel for Christmas). He hasn't invited her to his flat or given her a lift in his car. So far as I can see he hasn't done anything that a persistent 17 year old couldn't do. All his supposed power or authority mean nothing to a high-school girl living with her parents.
Age gap - is presented as a concern by numerous parties and immediately called 'creepy' by Ichika. So hardly presented uncritically. Koikimo is a very straight take on such a relationship, there is no fan service and little humour, so it gives the impression that it is trying to be taken seriously.
He threatens Tamaru - well, he glares at him. Not really an issue.
Summing up, I would say that this was not at all the 'creepy' anime it was being made out to be. It isn't anything I think people should be offended by, neither is it a masterpiece. I would say pretty average and personally I think the feels from Higehiro are superior, but the dynamics there are quite different as well.
