I guess everyone missing the point here

I trust the author basing from their prior works. The sex scene isn't done just for the sex. This isn't just to satisfy the readers for smut. It isn't as shallow as that. It shows Uruji's character and how he can be ugly as a human. Of course it's wrong to force yourself on somebody, I won't justify what he did. But taking into account his obsession towards Lamudan and how hard he worked to get him, that action stayed true to who he really is and has become over the years... plus the fact that he isn't entirely assured that Lamudan loves him back - first Lamudan said something like "who would love someone like you", second Lamudan chose Badom after the duel. Uruji probably has never imagined that Lamudan has already started to love him and so he acted rashly and asked for no excuses.

It's easy to ask for them to have more communication but it's never that easy when you're in the relationship itself, especially in this case where they started it awry, with unstable footing and reasons, unsure whether the other's feelings are reciprocated at all to the point of believing it won't be (Uruji's case), and unsure whether to believe they're really being loved (Lamudan's case, he did say even if he hears it from Uruji himself he'd probably still doubt why Uruji loves him).

It was implied afterwards that Uruji had reflected (based on what Lamudan said) and probably regrets it (hopefully). Let's wish they'd work everything out starting here with the right communication then on. Everything does not need to start perfectly for it to end great for the both of them.

You can have differing opinions about their relationship but please, this I ask you, please don't disregard the author's intentions as merely for "YAOI", for smut, for sex, cause if you think about it, it isn't. If you read their other works, you'd probably understand. They focus on the feelings of being human, a human in love and a human feeling feelings. Their works, I believe has been quite controversial as the ratings aren't always high and people leave with opposing opinions, but such is the reaction when you read something realistic and human-like. I hope you understand.