a theme of given is moving on from your past and thats what mafuyus doing, he said it clearly in his songs where he put sm effort into coming up with the lyrics emotionally- if he was using ue just as a replacement to yuki he wouldve started dating him soon after realizing his feelings, but he said in his songs that its hard cause he still remembers yuki but now hes let go of the past and is looking forward to the future if its with ue