Agreed, if there was no medical issue and no power dynamic, such as in the case of two adults, I would have no problem, but as it is, it does cause harm. However, there is no such issue in video games, including this one, so there is no problem. Selebus is doing extremely well in making us question the morality of our choices in LiL as any Denpa game developer should. This is one of the few games where I can't just shut off my emotions and morality because pixels, not humans, and it does make me want to take those pixels' feelings into consideration as well as the morality of my choices in game and the consequences for each choice. I will admit I am not taking my current play through seriously, but come v1.0, I will be doing so and it will most likely cause me to treat it as if these decisions and interactions were happening in real life. We all have Selebus to thank for that.The act of incest itself generally leads to inbreeding, which can have some pretty bad effects on the children and, after witnessing such effects, the mother by extention. There are a few other reasons why incest is a taboo in every culture, but discounting that, there's still another reason Sensei sleeping with Ami is wrong.
The power dynamic between Sensei and Ami's relationship is too one sided for it to develop into a proper romantic relationship. This will likely result in a really unhealthy relationship down the line.
Finally, part of the reason she does all those things to Sensei is because she has some pretty major parental issues. Ami doesn't need to get laid. She needs professional help.
Don't get me wrong. This shit is hot AF and I have gotten off to it. But it's still good to keep context for why these things are generally looked down upon in real life. Consent isn't the issue here.
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In terms of videogame logic, you're right. There are absolutely no points that say that having sex with Ami is the wrong choice or something bad to do. But that's kind of the point. Both us and Sensei see decisions in these games as only having short term minor consequences which can easily, or semi-easily, be undone while mostly being motivated by our libidos and/or desire to see more of the story/characters. However, a common theme in denpa games like this is to apply real world logic to the decisions made in them and treating the characters as if they're real people to show how messed up using that videogame logic can be.
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The writing alone makes this art, but I do agree with your point. I was one of those original bad homies and I did regret it, not because I missed out on a Rin event or two, though yes I felt bad for that, but because I hurt Rin herself, a feeling made much worse when she found out and told me off for it.If we're applying real world logic there is pretty much only 1 context that makes it "okay".
But I would echo Ankoku on this point, and it was the point I was trying to make by saying that Sensei is a predator; a logic much closer to the real world is being applied to the moral choices made by Sensei here than in your usual game.
The very fact that there are multiple posts now by people who were bad homies and regret it shows us that there are consequences for being a shitty person in the game - and the game is defining shitty much more strictly than a lot of people are used to.
And while my specific links have not yet been shamed I'm all on board for getting the treatment! It's what I signed up for by playing a game that is interested in analysing motivation and morality (at all when compared to most).
I can't believe I am about to type this about a porn game but the fact that this game is making us question at all the actions we take defines it as art rather than just smut.