Your first love is always difficult to get over, but there's usually a good outcome from it: life lessons, a friend to be there for you through it all, and wonderful memories. You catalogued all those memories with Yixing in your diary, and you're keeping it for a special day. Yixing was your first love, as he was yours, but what do you do when you two don't know how to evolve as a couple, or if you even have feelings for each other anymore?