yep.
it's building up to the brother having an argument but eventually relenting because the sister will stand for herself and for MC, and ultimately he has to respect his sister's decisions on who she wants to partner with, but then the cucked military guy will show up to reveal that MC is also fucking the princess, which will shock both the brother and sister, and this time there's absolutely no way the brother will let it slide and even the sister will feel betrayed, meanwhile the princess will also not going to say anything and accept the interpretation that she was a victim because she also feels betrayed by MC fucking the sister.
this interpretation will stick since the princess is still a virgin and everyone will understand this as the princess rejecting MC but MC forcing himself on her for anal lmao.