It was a one chapter in a manga where the uke and seme have been dating. The seme works in a office. I think the uke wanted to surprise or see his lover, but he sees a girl next to his lover( which it’s only the seme co-worker) it created a misunderstanding. It leads with the uke wanting to break up with him(which they don’t). It was the uke birthday and the seme wanted to surprise him by asking him to live together and they do.