Sumi isn't the bad one, but for me, he isn't exactly the good one either.
1) Heck, as much as I understand that their both suffering, Sumi chose to suffer (Going to those meetings to be raped and all that, nevermind his trauma/past experience). Utou may have loved the omega in the first story, but that omega already has a mate, he's in the process of moving on. + Tried his best? He gave up too easily, and started whoring himself out nevermind the consequences. He knows but still goes...
2) Sumi confessed, and proceeded to get out of the room, leaving Utou flabbergasted after striking all his points like that. Utou's human. You can't assume that just because your lover is already in love with you, he/she doesn't love the past person anymore, there's always that 5% left of that emotion that other ex-couples use to become friends again. Kissing scene afterwards, Utou says he's sorry (Entirely different meaning), Sumi's thoughts go a complete 360 and runs away (Not even clarifying). Like the ****, communication people. As someone who has been attacked with all my trigger points without getting a chance to talk, I get Utou more (Though I did talk to the other party the day afterwards + a slap to that other persons face) + I think the meeting they, if not for the cancelled flight, might've cleared everything between them. (Possibly)
3) The bite is definitely human, you can see by the teeth marks. It may or may not be consensual (Like they went drinking coz of him being sad and all that, got drunk, and you know what could happen), tho he wasn't in heat, so it's possible that it's not permanent. But then again who knows.
As for that last statement, I think Utou's scared, the last omega he loved went with an alpha, and Sumi is no different. He might be thinking that if he did go for Sumi, then Sumi went with an alpha in the end, he's still gonna be left behind. This is the complication I hate with Omegaverse, if a beta fell in love with an omega or alpha, the relationship will never be 100% especially because of the Fated-Pair syndrome thus making the relationship very fragile.
I do wish for this manga to end already, I hate being dragged on.
Can someone explain to me, why Sumi is the bad one? I've read comments saying that Utou deserves better, but don't you think that Sumi deserves better? Well,
1. Utou did love the omega before sumi (cant remember the name, Karasuma (?)), and Sumi tried his best to be an excellent subordinate to Utou, so that Utou can see him as he is.
2. After Sumi is confess, Utou didn't take any measure (he can grab sumi, and told him, he loves him and well, do things, its not like making sex in office is weird by now) but nope, he works first, sort his feeling and well, its too late.
3. we don't know if the bite is consensual bite or not, if consensual, why the heck sumi wait in front of Utou's house? (Plot twist: it's a friendly neighborhood's dog bite. not human, who knows?)
All I can see Sumi trying to love someone who still think Beta is not for Omega.. Wake Up Utou, it's almost 2019~!!