This information is found on the second page in the help section in the Skills menu.
I found the information on the forum. I did not find it where I wanted/expected it to be. The topic was not whether the information existed, but if it was where it needed to be. For me, it was not.
Academically smart people blundering in their private life is common. Being a psychologist doesn't make you immune to miss social cues and have a stable life yourself. Psychologist being the biggest whackos around is common in media.
The topic was not that Emma was blundering in her private life. The topic was that Emma failed to act reasonably as a psychologist in her job, i.e. regarding Monika and regarding the harassment claims in her workplace.
Cheating by itself gives away that its a risky move that can have drastic consequences. If you want to have a wholesome time with Leah, you don't cheat on her. If sooner or later she finds out, breaks up with you, your friends avoid you and you get a punishment in one way or another, its selfexplanotary.
The cheating doesn't add any of the stuff you mention though, it just adds more content to the game since you get to experience more paths. There's no risk, explanation of risk, no moments of almost getting caught, and no consequences yet. Players won't expect real life consequences if you don't present them with lifelike scenarios, hence the question.
MC doesn't enter in a serious relationship with anyone but Leah. Its casual with most of the girls, a secret with Jen and an affair with Kim.
You already get a cheating status effect later on that changes all stat gains in cunning, Kim in particular comments on your relationship with Leah.
The relationship with Jen is definitely serious, MC is risking his job for it. As for Kim I don't know, I didn't feel interested in following her path.