Y/n and Theseus used to date. They began dating during their time together at hogwarts and stayed together after graduation when Theseus went to go fight with the muggles in World War One. When he got back, however he wasn’t the same man she had known as he was unwilling to open up to her about the things he had gone through. Things seemed to be looking up, they had got engaged shortly after he returned y/n fell pregnant things were looking up for the couple they were planning a nursery and looking for a new home, but when y/n had a miscarriage he shut down and they couldn’t come back from that. They ended the engagement and went their separate ways. Eventually Theseus got engaged to leta me strange, but she was tragically murdered by Grindelwald. Fast forward to 1932 and y/n is called in by Dumbledore to help take down Grindelwald with Newt and his team. In order to take down Grindelwald she must face Theseus and be able to work alongside him and adress the trauma they went through together. Along the way the two begin to find their way back to eachother y/n opening up about things that happened during their relationship and Theseus processing his grief for Leta which y/n helps him heal from. In the end they slow burn fall back in love with eachother after realizing how well they work together and how much they know about each other and how they still love each other.