OK, after some hours of research, trials and errors, trying stuffs over and over. I discovered more or less how things works.
You cant get married if you are dating more than one character. If you are dating two or more you need to break with them leaving the one you want as a wife. You need a ring and the marriage register to get married. Ofc the very big house too. After get married ( no need the tailor, dunno the church ) all the girls you dated before and broke with them, will hate you, like very much.
While you are married, the other girls who you didnt date but liked you a lot will still doing so, but no matter what, they wont allow you cheat your wife, no even if you turn the city atmosphere is chaos side. The only one who is fine to have sex with you is Satira. Dunno how give to her the "affair" icon.
The girls who hate you so much because you broke with them, It is posible to raise their affection back, but at first only with their requested items ( rng, save before if you have the item ). After a long time, she will start accepting normal gifts and even join the party or have dates. Because lack of time, I wasnt able to make she show the heart of love to the mc yet. Maybe is harder than normal.
Like the dev said ingame, in this game you are free to do whatever you want. Prob there is more secrets and ways to "cheat" or something, but who knows. Oh btw, the only way to have a "harem" mode, is dating all girls, but without they find it out. Ofc you cant get married either because that imply you must choose one and leave the others.
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