so the guys in the second couple really cheated?????
no, no. both ends have never technically cheating on each other. their marriage was a political marriage and they made a consentual vow that they can get another person to be their another partner since the marriage was not based of love. mr lee is in love with mr seo since day one, but they agreed they would separate their feelings and marriage to different things and that should be underlined
mr seo never slept with anybody else unless that omega he dated since high school, so he kept up his promise. he didn't have any feelings toward mr lee at first but eventually love him after being together for all years
also, the baby is theirs. mr lee only said that it isn't mr seo's because he want to make hee-soo (mr seo's brother) shut up
so the guys in the second could couple cheated?