For me, ignoring the real answer of "it hasn't been written yet" for why Kiara isn't seeing any repercussions/getting noticed, I'm pretty sure it's a combination of her being normal human using non-powered methods to control the people, and the extremely small scale of her actions. Also, I'm pretty sure the canon timeframe of the game is at most a couple months, so her getting noticed already could be unlikely. While Kingston being a bad person doesn't justify her actions, it does sort of explain why nobody would look into what's going on with him. I'm pretty sure partner path Kiara will get a massive scolding from Sam for her actions somewhere down the line.
As for the city, I don't know that it's reasonable to say that making it more horny will lead to bad people doing (additional) bad things. I'd argue that a possible outcome to the entire city being less sexually inhibited would be there being less sexually frustrated individuals. That said, I'm not privy to secret elements of the game's worldbuilding, but I doubt Myscra wants to be writing a story where assault waits around every corner.