Nah, the big bro is an ass. He knew that his little brother was in love with the woman, so he secretly snatches her and then hits him with the "we want to marry"?? Hell, he told his friend that he likes her, before they even started to date, just to tell him to gtfo with his crush on him. Yet he hides everything from his lil bro, like it's some secret, until they are about to marry?? He didn't even give his brother the chance to come to terms with the situation or even decide wether he too, wants to pursue her. Like, that is just unfair. If it were some random other man, sure, but if it's your little brother, with whom you have a good relationship, then it's just a jerk move to sneak behind his back, knowing that you are going to hurt him a lot. Besides, it was pure bs when he talked about how Yuu just congratulated them with a smile, so he wasn't serious about her. What was he going to do, throw a tantrum?? She and his older brother were in a relationship long enough to decide to marry, what was Yuu supposed to do at that point, unless he wanted to tear appart the family?? The older bro sneaked behind Yuu's back like a coward, backed him into a corner, and then had the audacity to act, like he was right all along. He is just an ass. He said bs about pride and how he wasn't going to give her up, when in reality he was just afraid, that if they openly fought for her, his skill issue would cost him the woman, so instead he sneaked around like a thief and betrayed his brother.
Didn't even have the decency to move out with her, and just brought her home, where Yuu has no choice but live with them.
It also irked me, the way he handled Asahi. The moment he found a woman he liked, he quickly told Asahi to get him to fuck off, which, fine. But then he just drops contact? They were supposed to be friends, but he didn't have enough guts, to call up Asahi and keep contact with him. He was completely unbothered with them not speaking for over a year, and probably would have never reached out to Asahi, if they didn't meet accidentally. Even when they met, he clearly couldn't give less fucks about how they just went a year with no contact. You don't go from being friends, to not even knowing if the other person lives or dies or knows that you for effing married in the meantime (and hello, at least send him an invite?? Wtf), unless you really never cared about that person. Or perhaps he is just that much of a coward, that he was afraid to deal with an upset Asahi. I wouldn't be surprised, considering how much of a little sneaking, cowardly bitch he was towards his own brother.
Yuu is 1000% better than his brother, and Asahi is lucky that it was the younger brother he ended up with.