This right here is why Inusuku shelving the official translation sucks. I'm pretty sure both are a scare and the parents just tell him that to keep him away from his sister by inciting a sense of guilt. Remember that, for all intents and purposes due to no rape or otherwise forced encounters initiated by the MC, he didn't intend to impregnate her, so telling him that he successfully did would fill him with guilt and he would most likely stay away. Why a parent would ever do that to their own child, I don't know, this is just the best I can come up with while not knowing the actual intent of the dev in that scene. Japanese can be very contextual, so it is extremely difficult to correctly translate without working directly with the person who came up with the source material. A lot of things lose the meaning they had in Japanese when translated to English.There are two "pregnancy" endings.
1.) Bad End "Insemination" This one occurs when Imouto doesn't have enough trust, Onii-chan doesn't have enough cash, or both. Or You choose "W-We're not sure yet." She runs back home to mama, and there is a pregnancy, but the baby is never born, or so Onii-chan is told, and he never sees Imouto again.
2.) Good End "Happy Life" Here, the pregnancy was just a scare, and apparently Onii-chan gets an off-screen vasectomy, so there's never a risk of pregnancy again (regardless of Imouto's cycle), and the gameplay can continue. What makes an off-screen vasectomy the most likely explanation (for 1.9 and above) is that Imouto's aware that she won't be getting pregnant and quite a bit of the night-crawling dialog changes. Although the dialog when having sex in the bath does not change, Imouto's behavior does. Prior to the good end, her emotion goes down two points if you cum inside after she asks you not to. After, her emotional state doesn't change even though she still says "I can get pregnant you know."
Possibly, also there is the fact that the MC's cumming scenes don't change, so it is very likely that any preventative measures were taken by the sister.Or alternatively, Imouto has an IUD. Can explain the last parts, and also that vasectomies stop you from ejaculation, unless you actually mean Onii-chan can't do so after the good end sequence. (In which case, yikes.)
You're fine, most of us have quite a bit of free time right now. That theory wouldn't have surprised me in the least if you had been serious, this is Japan we're talking about.you guys are all WRONG... they definitely form a contract with a demon. in exchange for the fetus inside Imouto (at least when you cum inside and there was successfull insemination), they are given ethernal life and time loop (explains why the Imouto always go to school despite the increasing days)
edit : i got too much free time
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